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Authors:
(1) Revathy B S, Raman Research Institute, Bengaluru, 560080, Karnataka, India and Corresponding author;
(2) Victor Mukherjee, Department of Physical Sciences, Indian Institute of Science Education and Research Berhampur, Berhampur, 760010, Odisha, India;
(3) Uma Divakaran, Department of Physics, Indian Institute of Technology Palakkad, Palakkad, 678623, Kerala, India. Table of Links Abstract and 1 Introduction 2 Free fermionic model 3 Many body quantum Otto cycle 4 Universal scalings in work output 5 Transverse Ising model as working medium 6 Conclusion and References 6 Conclusion We construct a many body quantum Otto cycle with a WM that undergoes a quantum phase transition. The non-unitary strokes of the cycle are powered by finite temperature baths, while the unitary strokes involve driving the WM close to the critical point. This driving leads to nonadiabatic excitations which can be quantified using relative excess energy that follows universal scalings with the rate of driving as well as the temperature of the cold bath. The excess energy can be linked to the output work of the engine which thus manifests the universal scalings shown by the excess energy. Notably, we show that higher values of the cold bath temperature TC allows one to operate the engine close to the adiabatic limit for lower values of τ2 ≈ τmin, which further follows universal scaling relations. This raises interesting questions regarding the importance of control methods such as shortcuts to adiabaticity [41], or bath engineering [23], for finite temperature quantum heat engines. Furthermore, our results for one-dimensional transverse Ising model WM suggest the existence of an optimal value of the cold bath temperature TC > 0, for operating the QHE with high work output at high power. These counterintuitive results stem from the dominance of thermal fluctuations over quantum fluctuations in finite-temperature quantum critical heat engines, for higher bath temperatures. Acknowledgements. R.B.S. and U.D. acknowledge the use of HPC facility Chandra at IIT Palakkad. U.D. acknowledges support from SERB (SPG/2022/000708). V.M. acknowledges support from SERB through MATRICS (Project No. MTR/2021/000055) and a Seed Grant from IISER Berhampur. Data Availability Statement. Any data that support the findings of this study are included within the article. References [1] Jochen Gemmer, Mathias Michel, and G¨unter Mahler. Quantum thermodynamics: Emergence of thermodynamic behavior within composite quantum systems, volume 784. Springer, 2009. [2] Robert Alicki and Ronnie Kosloff. Introduction to Quantum Thermodynamics: History and Prospects. Springer International Publishing, 2018. [3] Sai Vinjanampathy and Janet Anders. Quantum thermodynamics. Contemporary Physics, 57:545, 2016. [4] Johannes Roßnagel, Samuel T. Dawkins, Karl N. Tolazzi, Obinna Abah, Eric Lutz, Ferdinand Schmidt-Kaler, and Kilian Singer. A single-atom heat engine. Science, 352(6283):325–329, 2016. [5] D. von Lindenfels, O. Grab, C. T. Schmiegelow, V. Kaushal, J. Schulz, Mark T. Mitchison, John Goold, F. Schmidt-Kaler, and U. G. Poschinger. Spin heat engine coupled to a harmonic-oscillator flywheel. Phys. Rev. Lett., 123:080602, Aug 2019. [6] John P. S. Peterson, Tiago B. Batalh˜ao, Marcela Herrera, Alexandre M. Souza, Roberto S. Sarthour, Ivan S. Oliveira, and Roberto M. Serra. Experimental characterization of a spin quantum heat engine. Phys. Rev. Lett., 123:240601, Dec 2019. [7] James Klatzow, Jonas N. Becker, Patrick M. Ledingham, Christian Weinzetl, Krzysztof T. Kaczmarek, Dylan J. Saunders, Joshua Nunn, Ian A. Walmsley, Raam Uzdin, and Eilon Poem. Experimental demonstration of quantum effects in the operation of microscopic heat engines. Phys. Rev. Lett., 122:110601, Mar 2019. [8] Obinna Abah and Eric Lutz. Optimal performance of a quantum otto refrigerator. Europhysics Letters, 113(6):60002, apr 2016. [9] Andreas Hartmann, Victor Mukherjee, Glen Bigan Mbeng, Wolfgang Niedenzu, and Wolfgang Lechner. Multi-spin counterdiabatic driving in many-body quantum otto refrigerators. Quantum, 4:377, 2020. [10] Thao P. Le, Jesper Levinsen, Kavan Modi, Meera M. Parish, and Felix A. Pollock. Spinchain model of a many-body quantum battery. Phys. Rev. A, 97:022106, Feb 2018. [11] Francesco Campaioli, Felix A. Pollock, and Sai Vinjanampathy. Quantum batteries - review chapter. arXiv: Quantum Physics, 2018. [12] Victor Montenegro, Marco G. Genoni, Abolfazl Bayat, and Matteo G. A. Paris. Quantum metrology with boundary time crystals. Communications Physics, 6(1):304, Oct 2023. [13] Karl Joulain, Jeremie Drevillon, Younes Ezzahri, and Jose Ordonez-Miranda. Quantum thermal transistor. Phys. Rev. Lett., 116:200601, May 2016. [14] Nikhil Gupt, Srijan Bhattacharyya, Bikash Das, Subhadeep Datta, Victor Mukherjee, and Arnab Ghosh. Floquet quantum thermal transistor. Phys. Rev. E, 106:024110, Aug 2022. [15] H. T. Quan, Yu-xi Liu, C. P. Sun, and Franco Nori. Quantum thermodynamic cycles and quantum heat engines. Phys. Rev. E, 76:031105, Sep 2007. [16] Ronnie Kosloff and Yair Rezek. The quantum harmonic otto cycle. Entropy, 19(4), 2017. [17] M. Campisi and R. Fazio. The power of a critical heat engine. Nat. Commun., 7:11895, 2016. [18] Thomas Fogarty and Thomas Busch. A many-body heat engine at criticality. Quantum Science and Technology, 6(1):015003, nov 2020. [19] Giulia Piccitto, Michele Campisi, and Davide Rossini. The ising critical quantum otto engine. New Journal of Physics, 2022. [20] Yu-Han Ma, Shan-He Su, and Chang-Pu Sun. Quantum thermodynamic cycle with quantum phase transition. Phys. Rev. E, 96:022143, Aug 2017. [21] Watanabe G. Yu YC Guan XW Chen, YY. and del Campo. An interaction-driven many particles quantum heat engine and its universal behavior. npj Quantum Inf, 5, 2019. [22] Revathy B.S, Victor Mukherjee, Uma Divakaran, and Adolfo del Campo. Universal finite-time thermodynamics of many-body quantum machines from kibble-zurek scaling. Phys. Rev. Res., 2:043247, 2020. [23] Revathy B.S, Victor Mukherjee, and Uma Divakaran. Bath engineering enhanced quantum critical engines. Entropy, 24(10), 2022. [24] Revathy B.S, Harsh Sharma, and Uma Divakaran. Improving performance of quantum heat engines by free evolution. arXiv preprint arXiv:2302.07003, 2023. [25] Jacek Dziarmaga. Dynamics of a quantum phase transition: Exact solution of the quantum ising model. Phys. Rev. Lett., 95:245701, Dec 2005. [26] Victor Mukherjee, Uma Divakaran, Amit Dutta, and Diptiman Sen. Quenching dynamics of a quantum xy spin- 1 2 chain in a transverse field. Phys. Rev. B, 76:174303, Nov 2007. [27] K. Sengupta, Diptiman Sen, and Shreyoshi Mondal. Exact results for quench dynamics and defect production in a two-dimensional model. Phys. Rev. Lett., 100:077204, Feb 2008. [28] Maximilian Keck, Simone Montangero, Giuseppe E Santoro, Rosario Fazio, and Davide Rossini. Dissipation in adiabatic quantum computers: lessons from an exactly solvable model. New Journal of Physics, 19(11):113029, nov 2017. [29] Souvik Bandyopadhyay, Sudarshana Laha, Utso Bhattacharya, and Amit Dutta. Exploring the possibilities of dynamical quantum phase transitions in the presence of a markovian bath. Scientific Reports, 8(1):11921, 2018. [30] Bogdan Damski and Wojciech H. Zurek. Adiabatic-impulse approximation for avoided level crossings: From phase-transition dynamics to landau-zener evolutions and back again. Phys. Rev. A, 73:063405, Jun 2006. [31] Anatoli Polkovnikov, Krishnendu Sengupta, Alessandro Silva, and Mukund Vengalattore. Colloquium: Nonequilibrium dynamics of closed interacting quantum systems. Rev. Mod. Phys., 83:863–883, Aug 2011. [32] Adolfo Del Campo and Wojciech H Zurek. Universality of phase transition dynamics: Topological defects from symmetry breaking. International Journal of Modern Physics A, 29(08):1430018, 2014. [33] Amit Dutta, Gabriel Aeppli, Bikas K Chakrabarti, Uma Divakaran, Thomas F Rosenbaum, and Diptiman Sen. Quantum phase transitions in transverse field spin models: from statistical physics to quantum information. Cambridge University Press, 2015. [34] A. Polkovnikov and V. Gritsev. Breakdown of the adiabatic limit in low-dimensional gapless systems. Nature Physics, 4:477, June 2008. [35] C. De Grandi, V. Gritsev, and A. Polkovnikov. Quench dynamics near a quantum critical point: Application to the sine-gordon model. Phys. Rev. B, 81:224301, Jun 2010. [36] C. De Grandi, V. Gritsev, and A. Polkovnikov. Quench dynamics near a quantum critical point. Phys. Rev. B, 81:012303, Jan 2010. [37] Shusa Deng, Gerardo Ortiz, and Lorenza Viola. Dynamical critical scaling and effective thermalization in quantum quenches: Role of the initial state. Phys. Rev. B, 83:094304, 2011. [38] Pierre Pfeuty. The one-dimensional ising model with a transverse field. Annals of Physics, 57(1):79 – 90, 1970. [39] J. E. Bunder and Ross H. McKenzie. Effect of disorder on quantum phase transitions in anisotropic xy spin chains in a transverse field. Phys. Rev. B, 60:344–358, Jul 1999. [40] Elliott Lieb, Theodore Schultz, and Daniel Mattis. Two soluble models of an antiferromagnetic chain. Annals of Physics, 16(3):407 – 466, 1961. [41] Andreas Hartmann, Victor Mukherjee, Wolfgang Niedenzu, and Wolfgang Lechner. Many-body quantum heat engines with shortcuts to adiabaticity. Phys. Rev. Res., 2:023145, May 2020. This paper is available on arxiv under CC BY 4.0 DEED license. Authors: (1) Revathy B S, Raman Research Institute, Bengaluru, 560080, Karnataka, India and Corresponding author; (2) Victor Mukherjee, Department of Physical Sciences, Indian Institute of Science Education and Research Berhampur, Berhampur, 760010, Odisha, India; (3) Uma Divakaran, Department of Physics, Indian Institute of Technology Palakkad, Palakkad, 678623, Kerala, India. Authors: Authors: (1) Revathy B S, Raman Research Institute, Bengaluru, 560080, Karnataka, India and Corresponding author; (2) Victor Mukherjee, Department of Physical Sciences, Indian Institute of Science Education and Research Berhampur, Berhampur, 760010, Odisha, India; (3) Uma Divakaran, Department of Physics, Indian Institute of Technology Palakkad, Palakkad, 678623, Kerala, India. Table of Links Abstract and 1 Introduction Abstract and 1 Introduction 2 Free fermionic model 2 Free fermionic model 3 Many body quantum Otto cycle 3 Many body quantum Otto cycle 4 Universal scalings in work output 4 Universal scalings in work output 5 Transverse Ising model as working medium 5 Transverse Ising model as working medium 6 Conclusion and References 6 Conclusion and References 6 Conclusion We construct a many body quantum Otto cycle with a WM that undergoes a quantum phase transition. The non-unitary strokes of the cycle are powered by finite temperature baths, while the unitary strokes involve driving the WM close to the critical point. This driving leads to nonadiabatic excitations which can be quantified using relative excess energy that follows universal scalings with the rate of driving as well as the temperature of the cold bath. The excess energy can be linked to the output work of the engine which thus manifests the universal scalings shown by the excess energy. Notably, we show that higher values of the cold bath temperature TC allows one to operate the engine close to the adiabatic limit for lower values of τ2 ≈ τmin, which further follows universal scaling relations. This raises interesting questions regarding the importance of control methods such as shortcuts to adiabaticity [41], or bath engineering [23], for finite temperature quantum heat engines. Furthermore, our results for one-dimensional transverse Ising model WM suggest the existence of an optimal value of the cold bath temperature TC > 0, for operating the QHE with high work output at high power. These counterintuitive results stem from the dominance of thermal fluctuations over quantum fluctuations in finite-temperature quantum critical heat engines, for higher bath temperatures. Acknowledgements . R.B.S. and U.D. acknowledge the use of HPC facility Chandra at IIT Palakkad. U.D. acknowledges support from SERB (SPG/2022/000708). V.M. acknowledges support from SERB through MATRICS (Project No. MTR/2021/000055) and a Seed Grant from IISER Berhampur. Acknowledgements Data Availability Statement. Any data that support the findings of this study are included within the article. Data Availability Statement. References [1] Jochen Gemmer, Mathias Michel, and G¨unter Mahler. Quantum thermodynamics: Emergence of thermodynamic behavior within composite quantum systems, volume 784. Springer, 2009. [2] Robert Alicki and Ronnie Kosloff. Introduction to Quantum Thermodynamics: History and Prospects. Springer International Publishing, 2018. [3] Sai Vinjanampathy and Janet Anders. Quantum thermodynamics. Contemporary Physics, 57:545, 2016. [4] Johannes Roßnagel, Samuel T. Dawkins, Karl N. Tolazzi, Obinna Abah, Eric Lutz, Ferdinand Schmidt-Kaler, and Kilian Singer. A single-atom heat engine. Science, 352(6283):325–329, 2016. [5] D. von Lindenfels, O. Grab, C. T. Schmiegelow, V. Kaushal, J. Schulz, Mark T. Mitchison, John Goold, F. Schmidt-Kaler, and U. G. Poschinger. Spin heat engine coupled to a harmonic-oscillator flywheel. Phys. Rev. Lett., 123:080602, Aug 2019. [6] John P. S. Peterson, Tiago B. Batalh˜ao, Marcela Herrera, Alexandre M. Souza, Roberto S. Sarthour, Ivan S. Oliveira, and Roberto M. Serra. Experimental characterization of a spin quantum heat engine. Phys. Rev. Lett., 123:240601, Dec 2019. [7] James Klatzow, Jonas N. Becker, Patrick M. Ledingham, Christian Weinzetl, Krzysztof T. Kaczmarek, Dylan J. Saunders, Joshua Nunn, Ian A. Walmsley, Raam Uzdin, and Eilon Poem. Experimental demonstration of quantum effects in the operation of microscopic heat engines. Phys. Rev. Lett., 122:110601, Mar 2019. [8] Obinna Abah and Eric Lutz. Optimal performance of a quantum otto refrigerator. Europhysics Letters, 113(6):60002, apr 2016. [9] Andreas Hartmann, Victor Mukherjee, Glen Bigan Mbeng, Wolfgang Niedenzu, and Wolfgang Lechner. Multi-spin counterdiabatic driving in many-body quantum otto refrigerators. Quantum, 4:377, 2020. [10] Thao P. Le, Jesper Levinsen, Kavan Modi, Meera M. Parish, and Felix A. Pollock. Spinchain model of a many-body quantum battery. Phys. Rev. A, 97:022106, Feb 2018. [11] Francesco Campaioli, Felix A. Pollock, and Sai Vinjanampathy. Quantum batteries - review chapter. arXiv: Quantum Physics, 2018. [12] Victor Montenegro, Marco G. Genoni, Abolfazl Bayat, and Matteo G. A. Paris. Quantum metrology with boundary time crystals. Communications Physics, 6(1):304, Oct 2023. [13] Karl Joulain, Jeremie Drevillon, Younes Ezzahri, and Jose Ordonez-Miranda. Quantum thermal transistor. Phys. Rev. Lett., 116:200601, May 2016. [14] Nikhil Gupt, Srijan Bhattacharyya, Bikash Das, Subhadeep Datta, Victor Mukherjee, and Arnab Ghosh. Floquet quantum thermal transistor. Phys. Rev. E, 106:024110, Aug 2022. [15] H. T. Quan, Yu-xi Liu, C. P. Sun, and Franco Nori. Quantum thermodynamic cycles and quantum heat engines. Phys. Rev. E, 76:031105, Sep 2007. [16] Ronnie Kosloff and Yair Rezek. The quantum harmonic otto cycle. Entropy, 19(4), 2017. [17] M. Campisi and R. Fazio. The power of a critical heat engine. Nat. Commun., 7:11895, 2016. [18] Thomas Fogarty and Thomas Busch. A many-body heat engine at criticality. Quantum Science and Technology, 6(1):015003, nov 2020. [19] Giulia Piccitto, Michele Campisi, and Davide Rossini. The ising critical quantum otto engine. New Journal of Physics, 2022. [20] Yu-Han Ma, Shan-He Su, and Chang-Pu Sun. Quantum thermodynamic cycle with quantum phase transition. Phys. Rev. E, 96:022143, Aug 2017. [21] Watanabe G. Yu YC Guan XW Chen, YY. and del Campo. An interaction-driven many particles quantum heat engine and its universal behavior. npj Quantum Inf, 5, 2019. [22] Revathy B.S, Victor Mukherjee, Uma Divakaran, and Adolfo del Campo. Universal finite-time thermodynamics of many-body quantum machines from kibble-zurek scaling. Phys. Rev. Res., 2:043247, 2020. [23] Revathy B.S, Victor Mukherjee, and Uma Divakaran. Bath engineering enhanced quantum critical engines. Entropy, 24(10), 2022. [24] Revathy B.S, Harsh Sharma, and Uma Divakaran. Improving performance of quantum heat engines by free evolution. arXiv preprint arXiv:2302.07003, 2023. [25] Jacek Dziarmaga. Dynamics of a quantum phase transition: Exact solution of the quantum ising model. Phys. Rev. Lett., 95:245701, Dec 2005. [26] Victor Mukherjee, Uma Divakaran, Amit Dutta, and Diptiman Sen. Quenching dynamics of a quantum xy spin- 1 2 chain in a transverse field. Phys. Rev. B, 76:174303, Nov 2007. [27] K. Sengupta, Diptiman Sen, and Shreyoshi Mondal. Exact results for quench dynamics and defect production in a two-dimensional model. Phys. Rev. Lett., 100:077204, Feb 2008. [28] Maximilian Keck, Simone Montangero, Giuseppe E Santoro, Rosario Fazio, and Davide Rossini. Dissipation in adiabatic quantum computers: lessons from an exactly solvable model. New Journal of Physics, 19(11):113029, nov 2017. [29] Souvik Bandyopadhyay, Sudarshana Laha, Utso Bhattacharya, and Amit Dutta. Exploring the possibilities of dynamical quantum phase transitions in the presence of a markovian bath. Scientific Reports, 8(1):11921, 2018. [30] Bogdan Damski and Wojciech H. Zurek. Adiabatic-impulse approximation for avoided level crossings: From phase-transition dynamics to landau-zener evolutions and back again. Phys. Rev. A, 73:063405, Jun 2006. [31] Anatoli Polkovnikov, Krishnendu Sengupta, Alessandro Silva, and Mukund Vengalattore. Colloquium: Nonequilibrium dynamics of closed interacting quantum systems. Rev. Mod. Phys., 83:863–883, Aug 2011. [32] Adolfo Del Campo and Wojciech H Zurek. Universality of phase transition dynamics: Topological defects from symmetry breaking. International Journal of Modern Physics A, 29(08):1430018, 2014. [33] Amit Dutta, Gabriel Aeppli, Bikas K Chakrabarti, Uma Divakaran, Thomas F Rosenbaum, and Diptiman Sen. Quantum phase transitions in transverse field spin models: from statistical physics to quantum information. Cambridge University Press, 2015. [34] A. Polkovnikov and V. Gritsev. Breakdown of the adiabatic limit in low-dimensional gapless systems. Nature Physics, 4:477, June 2008. [35] C. De Grandi, V. Gritsev, and A. Polkovnikov. Quench dynamics near a quantum critical point: Application to the sine-gordon model. Phys. Rev. B, 81:224301, Jun 2010. [36] C. De Grandi, V. Gritsev, and A. Polkovnikov. Quench dynamics near a quantum critical point. Phys. Rev. B, 81:012303, Jan 2010. [37] Shusa Deng, Gerardo Ortiz, and Lorenza Viola. Dynamical critical scaling and effective thermalization in quantum quenches: Role of the initial state. Phys. Rev. B, 83:094304, 2011. [38] Pierre Pfeuty. The one-dimensional ising model with a transverse field. Annals of Physics, 57(1):79 – 90, 1970. [39] J. E. Bunder and Ross H. McKenzie. Effect of disorder on quantum phase transitions in anisotropic xy spin chains in a transverse field. Phys. Rev. B, 60:344–358, Jul 1999. [40] Elliott Lieb, Theodore Schultz, and Daniel Mattis. Two soluble models of an antiferromagnetic chain. Annals of Physics, 16(3):407 – 466, 1961. [41] Andreas Hartmann, Victor Mukherjee, Wolfgang Niedenzu, and Wolfgang Lechner. Many-body quantum heat engines with shortcuts to adiabaticity. Phys. Rev. Res., 2:023145, May 2020. This paper is available on arxiv under CC BY 4.0 DEED license. This paper is available on arxiv under CC BY 4.0 DEED license. available on arxiv

Quantum Critical Engine at Finite Temperatures: Conclusion and References

My name is Marina, and I've been designing for over a decade. Three years ago, I entered the gaming industry and have been working in it since. Before this, I knew virtually nothing about games and their specific design needs. How surprised I was when I got an inside look! And I haven't stopped being surprised to this day. It turns out that, in most cases, communication design in the gaming industry lags far behind other fields. By communication design, I mean identity, websites, and any micro media like banners, newsletters, and covers. In this article, I explore why the leaders of the CG world remain on the margins of communication design. What areas of design suck in GameDev (TLDR: all of them)? As I mentioned, all communication design suffers. In this breakdown, I focused on what users and players encounter most often - websites. First, I'll provide concrete evidence by showing examples of poor design. I'll critique a few well-known publishers, developers, and recent games. Then, I'll speculate from my experience as to why this deplorable design persists. Even the world giants don't try! Of course, you might think of incredibly stylish sites related to Game Development and say, "Marina, you are treacherously deceiving us!" Yes, there are stylish projects, and I like them a lot, but they are few! By the way, I included some chic projects as examples at the end of the article. But let's look at the global industry as a whole. Even the giants don't really care about the visual quality of their media. I will analyse examples from Rockstar, EA, and CD Projekt Red, highlighting what is good and what is bad in their designs. EA One of the first companies in the industry, EA is among the top 5 game companies in America and Europe in terms of revenue and market capitalisation. It's a very solid company. Now look at the website. It doesn't look solid at all. Such layouts were popular in 2010: a header on half of the first screen and then a tile of pictures. Earlier it was cool because it was clean and minimalistic, but now even website constructors offer more interesting options. Rockstar Rockstar is an American video game company, recognised as an industry leader thanks to hits like GTA, Red Dead Redemption, and Max Payne. Rockstar is renowned for its meticulously crafted game worlds. But the website is the direct opposite of the games. I want to shout, "Guys, be rock stars! You have colossal resources and the greatest games!" On the website, we see the same layout: a big header and tiles underneath it. But there's an interesting nuance. The header isn't just an image; it's a slider. And the slider has a crooked grid: the picture on the left side doesn't match the end of the picture in the grid. The column on the right side is virtually empty and meaningless: the space is practically unused, and because of the colour, it merges with the background of the rest of the page. CD Projekt Red A Polish studio known primarily for The Witcher and Cyberpunk. They managed to get Keanu Reeves into their game but couldn't make a really cool website for themselves. Unlike the examples above, instead of an inarticulate header, they have a spectacular full-front screen video. Almost everyone in the industry is fine with CG: really talented people are doing art, motion, and concepts. But you have to scroll down, and what do we see? Tiles from 2010. Again! Conclusion on the biggest companies As we can see, even the giants aren't trying. This is bad for the industry as a whole because they set the style and direction for smaller studios. Imagine yourself as a studio looking at a huge, powerful company that sells this kind of visual media design. You think, "Well, since they're selling it, then we shouldn't bother either." Like the rock star, so is the music. What about design for smaller companies? Okay, we've realised that global companies are way behind. But big, complex projects are often slow and clunky. So let's look at those who are quicker - medium and small studios. What do they have in terms of design? In 80% of cases, it's the same as the leaders - dull layouts and tiles. Below, I'll just attach examples. Why is it bad with GameDev? I've been wondering why the sphere is so blatantly stagnant while others are actively developing. Projects in e-commerce or IT are wildly experimenting with meanings, techniques, forms, and layouts, while the game industry is stuck in 2014 when it comes to website development. Although it would seem that game sites are a better place to introduce new things: the audience is loyal and interactive by default. It's a whole field for experimentation! But no, blocks and standard narratives. It's a shame about the missed opportunities. I've highlighted two bold reasons for the stagnation: Publishers don't like to take risks and waste money. They don't want to touch something that works and consistently makes good money.
GameDev is rolling along on familiar rails. The industry is used to making high-quality, beautiful, very professional, and attractive key arts and using them to sell the product. Unfortunately, what's often overlooked is that design is also an excellent tool for selling and forming the brand's image. Especially if it's not only about the picture but also about the idea. It makes me sad to watch the industry from both a player's and a specialist's point of view. But I believe that good will prevail and we will see a market filled with cool products! In the meantime, I'm going to go through Disco Elysium for the third time. While I play and weep, as promised, here are examples of very cool projects worthy of all design respect. Design in GameDev that doesn’t suck Kepler A little-known publisher but with well-known projects: the studio that nailed Sifu is developing under them. Take a look at their addictive and enjoyable site. It has a super stylish design, lots of micro-animations, and interactivity. The layout is in the best traditions of festival projects. All in all, it's something to strive for in terms of visuals! AXOLOT A small studio based in Stockholm. Everything about this site is beautiful! Look at the preloader - precision animation, strong graphics, calibrated to the pixel! My inner graphic designer is in awe! The detail, the micro typography, the crazy interactive flying 3D—there's style in this. There's power to the brand—it makes you want to linger on the site to scrutinize every pixel for an interesting passphrase or solution. I give it 10 awwwards out of 10! A studio from Sweden has not shamed the great and mighty Swiss design. Belka Games Belarusians who could do it! Although they make mobile games, they do it with style! The site immediately makes it clear that there will be no serious shooters or huge open worlds here. The site is honest, beautiful, and simple, and that's what pays off. Special kudos for the custom typography and cool illustrations! My name is Marina, and I've been designing for over a decade. Three years ago, I entered the gaming industry and have been working in it since. Before this, I knew virtually nothing about games and their specific design needs. How surprised I was when I got an inside look! And I haven't stopped being surprised to this day. My name is Marina, and I've been designing for over a decade. Three years ago, I entered the gaming industry and have been working in it since. Before this, I knew virtually nothing about games and their specific design needs. How surprised I was when I got an inside look! And I haven't stopped being surprised to this day. It turns out that, in most cases, communication design in the gaming industry lags far behind other fields. By communication design, I mean identity, websites, and any micro media like banners, newsletters, and covers. In this article, I explore why the leaders of the CG world remain on the margins of communication design. What areas of design suck in GameDev (TLDR: all of them)? What areas of design suck in GameDev (TLDR: all of them)? As I mentioned, all communication design suffers. In this breakdown, I focused on what users and players encounter most often - websites. First, I'll provide concrete evidence by showing examples of poor design. I'll critique a few well-known publishers, developers, and recent games. Then, I'll speculate from my experience as to why this deplorable design persists. Even the world giants don't try! Even the world giants don't try! Of course, you might think of incredibly stylish sites related to Game Development and say, "Marina, you are treacherously deceiving us!" Yes, there are stylish projects, and I like them a lot, but they are few! By the way, I included some chic projects as examples at the end of the article. But let's look at the global industry as a whole. Even the giants don't really care about the visual quality of their media. I will analyse examples from Rockstar, EA, and CD Projekt Red, highlighting what is good and what is bad in their designs. EA EA One of the first companies in the industry, EA is among the top 5 game companies in America and Europe in terms of revenue and market capitalisation. One of the first companies in the industry, EA is among the top 5 game companies in America and Europe in terms of revenue and market capitalisation. It's a very solid company. Now look at the website. It doesn't look solid at all. Such layouts were popular in 2010: a header on half of the first screen and then a tile of pictures. Earlier it was cool because it was clean and minimalistic, but now even website constructors offer more interesting options. Rockstar Rockstar Rockstar is an American video game company, recognised as an industry leader thanks to hits like GTA, Red Dead Redemption, and Max Payne. Rockstar is an American video game company, recognised as an industry leader thanks to hits like GTA, Red Dead Redemption, and Max Payne. Rockstar is renowned for its meticulously crafted game worlds. But the website is the direct opposite of the games. I want to shout, "Guys, be rock stars! You have colossal resources and the greatest games!" Rockstar is renowned for its meticulously crafted game worlds. But the website is the direct opposite of the games. I want to shout, "Guys, be rock stars! You have colossal resources and the greatest games!" On the website, we see the same layout: a big header and tiles underneath it. But there's an interesting nuance. The header isn't just an image; it's a slider. And the slider has a crooked grid: the picture on the left side doesn't match the end of the picture in the grid. The column on the right side is virtually empty and meaningless: the space is practically unused, and because of the colour, it merges with the background of the rest of the page. CD Projekt Red CD Projekt Red A Polish studio known primarily for The Witcher and Cyberpunk. They managed to get Keanu Reeves into their game but couldn't make a really cool website for themselves. A Polish studio known primarily for The Witcher and Cyberpunk. They managed to get Keanu Reeves into their game but couldn't make a really cool website for themselves. Unlike the examples above, instead of an inarticulate header, they have a spectacular full-front screen video. Almost everyone in the industry is fine with CG: really talented people are doing art, motion, and concepts. But you have to scroll down, and what do we see? Tiles from 2010. Again! Conclusion on the biggest companies Conclusion on the biggest companies As we can see, even the giants aren't trying. This is bad for the industry as a whole because they set the style and direction for smaller studios. Imagine yourself as a studio looking at a huge, powerful company that sells this kind of visual media design. You think, "Well, since they're selling it, then we shouldn't bother either." Like the rock star, so is the music. What about design for smaller companies? What about design for smaller companies? Okay, we've realised that global companies are way behind. But big, complex projects are often slow and clunky. So let's look at those who are quicker - medium and small studios. What do they have in terms of design? In 80% of cases, it's the same as the leaders - dull layouts and tiles. Below, I'll just attach examples. Why is it bad with GameDev? Why is it bad with GameDev? I've been wondering why the sphere is so blatantly stagnant while others are actively developing. Projects in e-commerce or IT are wildly experimenting with meanings, techniques, forms, and layouts, while the game industry is stuck in 2014 when it comes to website development. Although it would seem that game sites are a better place to introduce new things: the audience is loyal and interactive by default. It's a whole field for experimentation! But no, blocks and standard narratives. It's a shame about the missed opportunities. I've highlighted two bold reasons for the stagnation: I've highlighted two bold reasons for the stagnation: Publishers don't like to take risks and waste money. They don't want to touch something that works and consistently makes good money. GameDev is rolling along on familiar rails. The industry is used to making high-quality, beautiful, very professional, and attractive key arts and using them to sell the product. Unfortunately, what's often overlooked is that design is also an excellent tool for selling and forming the brand's image. Especially if it's not only about the picture but also about the idea. Publishers don't like to take risks and waste money. They don't want to touch something that works and consistently makes good money. GameDev is rolling along on familiar rails. The industry is used to making high-quality, beautiful, very professional, and attractive key arts and using them to sell the product. Unfortunately, what's often overlooked is that design is also an excellent tool for selling and forming the brand's image. Especially if it's not only about the picture but also about the idea. It makes me sad to watch the industry from both a player's and a specialist's point of view. But I believe that good will prevail and we will see a market filled with cool products! In the meantime, I'm going to go through Disco Elysium for the third time. While I play and weep, as promised, here are examples of very cool projects worthy of all design respect. Design in GameDev that doesn’t suck Design in GameDev that doesn’t suck Kepler Kepler A little-known publisher but with well-known projects: the studio that nailed Sifu is developing under them. Take a look at their addictive and enjoyable site. It has a super stylish design, lots of micro-animations, and interactivity. The layout is in the best traditions of festival projects. All in all, it's something to strive for in terms of visuals! AXOLOT AXOLOT A small studio based in Stockholm. Everything about this site is beautiful! Look at the preloader - precision animation, strong graphics, calibrated to the pixel! My inner graphic designer is in awe! The detail, the micro typography, the crazy interactive flying 3D—there's style in this. There's power to the brand—it makes you want to linger on the site to scrutinize every pixel for an interesting passphrase or solution. I give it 10 awwwards out of 10! A studio from Sweden has not shamed the great and mighty Swiss design. Belka Games Belka Games Belarusians who could do it! Although they make mobile games, they do it with style! The site immediately makes it clear that there will be no serious shooters or huge open worlds here. The site is honest, beautiful, and simple, and that's what pays off. Special kudos for the custom typography and cool illustrations!

Everything Wrong With Web Design in GameDev

GameDev এ ওয়েব ডিজাইনের সাথে সবকিছু ভুল

Alles, was beim Webdesign in der Spieleentwicklung schiefläuft

Todo lo que está mal en el diseño web en GameDev

Tout ce qui ne va pas avec la conception Web dans le développement de jeux

गेमडेव में वेब डिज़ाइन के साथ सब कुछ गलत है

ゲーム開発におけるウェブデザインの問題点

GameDev에서 웹 디자인의 모든 문제

Tudo de errado com web design em GameDev

Все, что не так с веб-дизайном в GameDev

GameDev'de Web Tasarımında Yanlış Olan Her Şey

Mọi thứ sai với thiết kế web trong GameDev

GameDev 中网页设计的所有错误

Thermodynamic Limits Around M-dwarf Stars: Acknowledgements

This paper is available on arxiv under CC 4.0 license.
Authors:
(1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk);
(2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK;
(3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia;
(4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. Table of Links Abstract and Intro
Observation
Orbital Ephemeris
Radial Velocity Analysis
Spectral Analysis
Analysis of the Light Curve
Physical Properties
Asteroseismic Analysis
Discussion
Conclusion, Data Availability, Acknowledgments, and References
Appendix A: Ephemeris Determination
Appendix B: Iteratively Prewhitened Frequencies
Appendix C: Detected Tidally Perturbed Pulsations 2 OBSERVATIONS 2.1 Photometry The Kepler space telescope (Koch et al. 2010) was launched in March 2009 with the primary aim of detecting Earth-like extrasolar planets around solar-like stars. However, the mission has also provided a huge amount of high-quality data on stars and stellar systems (Hong et al. 2022). The data were collected using two modes of observation (Gilliland et al. 2010), long cadence (29.5 min sampling rate) and short cadence (58.5 s sampling rate). To keep the ht). solar arrays pointed toward the Sun during its Earth-trailing heliocentric orbit, the spacecraft was rotated by 90◦ every three months (one quarter). Primary functions of the Kepler photometric analysis module of the Kepler science data processing pipeline are responsible for generating the Simple Aperture Photometric (SAP) flux time series of the observed objects, while secondary photometric analysis functions performed by the Pre-Search Data Conditioning (PDC) module support systematic error correction, giving rise to the PDCSAP fluxes (see Jenkins 2017, for further details on the SAP and PDCSAP measurements). KIC 9851944 was observed by Kepler in six quarters (0, 12, 13, 16). The light curves from the Kepler quarters and TESS sectors mentioned above were downloaded from the Mikulski Archive for Space Telescopes (MAST) and are used in Section 3 to determine the ephemeris of the system, as well as Section 6 to obtain the final model of the light curve. Both SAP and PDCSAP measurements are available; the SAP and PDCSAP fluxes were similar, which we verified by inspecting the SAP fluxes with the PDCSAP fluxes overplotted after dividing them by their median flux values to put them on the same scale. Thus, we used the SAP measurements to avoid possible biases due to the additional processing applied to the PDCSAP data. A second-order polynomial was fitted to fluxes that correspond to positions of quadrature, i.e., the maximum of the ellipsoidal brightening, to estimate systematic trends present in the light curves. Subtracting the difference between this polynomial and the median flux of the light curve yields a model for the local median level of out-of-eclipse flux. This model was then divided out to remove systematic trends. The residual value of a smoothed version of the light curve subtracted from the observed light curve was calculated and observed fluxes that deviated by more than 1% were rejected. Fluxes were converted to magnitudes and errors were propagated following Prša (2018). The short cadence Kepler light curve from Quarter 0 and the two-minute cadence TESS light curve from Sector 15, after performing these operations, are shown in the top and middle panels of Fig.1, respectively. ely. KIC 9851944 was also observed by the Wide Angle Search for Planets (WASP) telescope (Butters et al. 2010) between May 2007 and July 2010. WASP consisted of two robotic observatories, one in the Nothern Hemisphere at Observatorio del Roque de los Muchachos on La Palma and the other at the South African Astronomical Observatory (SAAO), each with eight 20 mm telescopes on a single mount. Observations of KIC 9851944 collected by WASP between May 2007 and July 2007 as well as between June 2008 and July 2008 are shown in the bottom panels of Fig.1 phase folded about the orbital period determined in Section 3. The data collected by WASP for KIC 9851944 were only used to constrain the times of primary minima when performing preliminary fits to the Kepler and TESS light curves in Section 3, to determine the orbital ephemeris. 2.2 Spectroscopy A set of 33 spectroscopic observations were obtained for the target using the Hamilton échelle spectrograph (Vogt 1987) on the Shane 3 m telescope at Lick Observatory during two observing runs, one in July 2012 and the other in June 2013. The data were obtained using CCD chip no. 4, giving a wavelength coverage of 340 – 900 nm over 89 échelle orders at a resolving power of R ≈ 60000. The data were reduced using the standard pipeline for the spectrograph (e.g. Fischer et al. 2014). Flat fields were obtained with a quartz lamp and divided from the spectra. The wavelength calibration was obtained from exposures of a thorium-argon emission lamp taken roughly every hour during the night. Details for the normalization of the one-dimensional extracted spectra are given in Sections 4 and 5 because each of those components of the analysis used different approaches. Table 1 gives the epochs of each of the 33 spectrosopic observations as well as the signal-to-noise ratio (S/N), estimated as the square root of the counts close to the peak of the best-exposed échelle order. Also given are the corresponding RVs of each component that are derived in Section 4. This paper is available on arxiv under CC 4.0 license. Authors: (1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk); (2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK; (3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. This paper is available on arxiv under CC 4.0 license. Authors: Authors: (1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk); (2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK; (3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. Table of Links Abstract and Intro Observation Orbital Ephemeris Radial Velocity Analysis Spectral Analysis Analysis of the Light Curve Physical Properties Asteroseismic Analysis Discussion Conclusion, Data Availability, Acknowledgments, and References Appendix A: Ephemeris Determination Appendix B: Iteratively Prewhitened Frequencies Appendix C: Detected Tidally Perturbed Pulsations Abstract and Intro Abstract and Intro Observation Observation Orbital Ephemeris Orbital Ephemeris Radial Velocity Analysis Radial Velocity Analysis Spectral Analysis Spectral Analysis Analysis of the Light Curve Analysis of the Light Curve Physical Properties Physical Properties Asteroseismic Analysis Asteroseismic Analysis Discussion Discussion Conclusion, Data Availability, Acknowledgments, and References Conclusion, Data Availability, Acknowledgments, and References Appendix A: Ephemeris Determination Appendix A: Ephemeris Determination Appendix B: Iteratively Prewhitened Frequencies Appendix B: Iteratively Prewhitened Frequencies Appendix C: Detected Tidally Perturbed Pulsations Appendix C: Detected Tidally Perturbed Pulsations 2 OBSERVATIONS 2.1 Photometry The Kepler space telescope (Koch et al. 2010) was launched in March 2009 with the primary aim of detecting Earth-like extrasolar planets around solar-like stars. However, the mission has also provided a huge amount of high-quality data on stars and stellar systems (Hong et al. 2022). The data were collected using two modes of observation (Gilliland et al. 2010), long cadence (29.5 min sampling rate) and short cadence (58.5 s sampling rate). To keep the ht). solar arrays pointed toward the Sun during its Earth-trailing heliocentric orbit, the spacecraft was rotated by 90◦ every three months (one quarter). Primary functions of the Kepler photometric analysis module of the Kepler science data processing pipeline are responsible for generating the Simple Aperture Photometric (SAP) flux time series of the observed objects, while secondary photometric analysis functions performed by the Pre-Search Data Conditioning (PDC) module support systematic error correction, giving rise to the PDCSAP fluxes (see Jenkins 2017, for further details on the SAP and PDCSAP measurements). KIC 9851944 was observed by Kepler in six quarters (0, 12, 13, Kepler 16). The light curves from the Kepler quarters and TESS sectors mentioned above were downloaded from the Mikulski Archive for Space Telescopes (MAST) and are used in Section 3 to determine the ephemeris of the system, as well as Section 6 to obtain the final model of the light curve. Both SAP and PDCSAP measurements are available; the SAP and PDCSAP fluxes were similar, which we verified by inspecting the SAP fluxes with the PDCSAP fluxes overplotted after dividing them by their median flux values to put them on the same scale. Thus, we used the SAP measurements to avoid possible biases due to the additional processing applied to the PDCSAP data. A second-order polynomial was fitted to fluxes that correspond to positions of quadrature, i.e., the maximum of the ellipsoidal brightening, to estimate systematic trends present in the light curves. Subtracting the difference between this polynomial and the median flux of the light curve yields a model for the local median level of out-of-eclipse flux. This model was then divided out to remove systematic trends. The residual value of a smoothed version of the light curve subtracted from the observed light curve was calculated and observed fluxes that deviated by more than 1% were rejected. Fluxes were converted to magnitudes and errors were propagated following Prša (2018). The short cadence Kepler light curve from Quarter 0 and the two-minute cadence TESS light curve from Sector 15, after performing these operations, are shown in the top and middle panels of Fig.1, respectively. ely. KIC 9851944 was also observed by the Wide Angle Search for Planets (WASP) telescope (Butters et al. 2010) between May 2007 and July 2010. WASP consisted of two robotic observatories, one in the Nothern Hemisphere at Observatorio del Roque de los Muchachos on La Palma and the other at the South African Astronomical Observatory (SAAO), each with eight 20 mm telescopes on a single mount. Observations of KIC 9851944 collected by WASP between May 2007 and July 2007 as well as between June 2008 and July 2008 are shown in the bottom panels of Fig.1 phase folded about the orbital period determined in Section 3. The data collected by WASP for KIC 9851944 were only used to constrain the times of primary minima when performing preliminary fits to the Kepler and TESS light curves in Section 3, to determine the orbital ephemeris. 2.2 Spectroscopy A set of 33 spectroscopic observations were obtained for the target using the Hamilton échelle spectrograph (Vogt 1987) on the Shane 3 m telescope at Lick Observatory during two observing runs, one in July 2012 and the other in June 2013. The data were obtained using CCD chip no. 4, giving a wavelength coverage of 340 – 900 nm over 89 échelle orders at a resolving power of R ≈ 60000. The data were reduced using the standard pipeline for the spectrograph (e.g. Fischer et al. 2014). Flat fields were obtained with a quartz lamp and divided from the spectra. The wavelength calibration was obtained from exposures of a thorium-argon emission lamp taken roughly every hour during the night. Details for the normalization of the one-dimensional extracted spectra are given in Sections 4 and 5 because each of those components of the analysis used different approaches. Table 1 gives the epochs of each of the 33 spectrosopic observations as well as the signal-to-noise ratio (S/N), estimated as the square root of the counts close to the peak of the best-exposed échelle order. Also given are the corresponding RVs of each component that are derived in Section 4.

Physical Properties of the Eclipsing Binary KIC 9851944: Observation

Physical Properties of the Eclipsing Binary KIC 9851944: Abstract and Intro

This paper is available on arxiv under CC 4.0 license.
Authors:
(1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk);
(2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK;
(3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia;
(4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. Table of Links Abstract and Intro
Observation
Orbital Ephemeris
Radial Velocity Analysis
Spectral Analysis
Analysis of the Light Curve
Physical Properties
Asteroseismic Analysis
Discussion
Conclusion, Data Availability, Acknowledgments, and References
Appendix A: Ephemeris Determination
Appendix B: Iteratively Prewhitened Frequencies
Appendix C: Detected Tidally Perturbed Pulsations 8 ASTEROSEISMIC ANALYSIS 8.1 Frequency analysis Following the binary modelling, we continue with the asteroseismic analysis of the target. Because the observed pulsations have much smaller amplitudes than the binary signal, the quality of the TESS and WASP data are insufficient for the asteroseismic analysis, and we limit ourselves to using the residual Kepler light curve. This is the merged light curve of all available Kepler short-cadence data after subtracting the best-fitting binary model, hereafter referred to as the pulsation light curve. To minimize the impact of outliers and instrumental effects on the asteroseismic analysis of small-amplitude pulsations, we apply additional processing to the data. Firstly, we remove those parts where coronal mass ejections (CMEs) or thermal and pointing changes of the spacecraft, such as at the start of a quarter or after a safe-mode event, have a visible impact on the quality of the light curve. Secondly, we apply preliminary iterative pre-whitening (as described by, e.g., Van Reeth et al. 2023) to build a tentative mathematical model of the 20 most dominant pulsations using a sum of sine waves 8.2 Tidal perturbation analysis 8.3 Orbital harmonic frequencies As pointed out by Guo et al. (2016), the detection of an orbital harmonic frequency comb is somewhat unexpected for synchronised binaries with circular orbits, though it has also been detected for other such systems (da Silva et al. 2014). Because the orbital eccentricity of the binary is zero, the equilibrium tides that are responsible for deforming the star and perturbing the pulsations are considerably larger than the dynamical tides that excite oscillations. Hence, this can indicate that this system has a slightly eccentric orbit or that one or both of the components is asynchronously rotating, within the uncertainty margins of our measurements. 8.4 Gravity-mode period-spacing pattern The error margins are smaller than the symbol sizes. This paper is available on arxiv under CC 4.0 license. Authors: (1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk); (2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK; (3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. This paper is available on arxiv under CC 4.0 license. Authors: Authors: (1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk); (2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK; (3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. Table of Links Abstract and Intro Observation Orbital Ephemeris Radial Velocity Analysis Spectral Analysis Analysis of the Light Curve Physical Properties Asteroseismic Analysis Discussion Conclusion, Data Availability, Acknowledgments, and References Appendix A: Ephemeris Determination Appendix B: Iteratively Prewhitened Frequencies Appendix C: Detected Tidally Perturbed Pulsations Abstract and Intro Abstract and Intro Observation Observation Orbital Ephemeris Orbital Ephemeris Radial Velocity Analysis Radial Velocity Analysis Spectral Analysis Spectral Analysis Analysis of the Light Curve Analysis of the Light Curve Physical Properties Physical Properties Asteroseismic Analysis Asteroseismic Analysis Discussion Discussion Conclusion, Data Availability, Acknowledgments, and References Conclusion, Data Availability, Acknowledgments, and References Appendix A: Ephemeris Determination Appendix A: Ephemeris Determination Appendix B: Iteratively Prewhitened Frequencies Appendix B: Iteratively Prewhitened Frequencies Appendix C: Detected Tidally Perturbed Pulsations Appendix C: Detected Tidally Perturbed Pulsations 8 ASTEROSEISMIC ANALYSIS 8.1 Frequency analysis Following the binary modelling, we continue with the asteroseismic analysis of the target. Because the observed pulsations have much smaller amplitudes than the binary signal, the quality of the TESS and WASP data are insufficient for the asteroseismic analysis, and we limit ourselves to using the residual Kepler light curve. This is the merged light curve of all available Kepler short-cadence data after subtracting the best-fitting binary model, hereafter referred to as the pulsation light curve. To minimize the impact of outliers and instrumental effects on the asteroseismic analysis of small-amplitude pulsations, we apply additional processing to the data. Firstly, we remove those parts where coronal mass ejections (CMEs) or thermal and pointing changes of the spacecraft, such as at the start of a quarter or after a safe-mode event, have a visible impact on the quality of the light curve. Secondly, we apply preliminary iterative pre-whitening (as described by, e.g., Van Reeth et al. 2023) to build a tentative mathematical model of the 20 most dominant pulsations using a sum of sine waves 8.2 Tidal perturbation analysis 8.3 Orbital harmonic frequencies As pointed out by Guo et al. (2016), the detection of an orbital harmonic frequency comb is somewhat unexpected for synchronised binaries with circular orbits, though it has also been detected for other such systems (da Silva et al. 2014). Because the orbital eccentricity of the binary is zero, the equilibrium tides that are responsible for deforming the star and perturbing the pulsations are considerably larger than the dynamical tides that excite oscillations. Hence, this can indicate that this system has a slightly eccentric orbit or that one or both of the components is asynchronously rotating, within the uncertainty margins of our measurements. 8.4 Gravity-mode period-spacing pattern The error margins are smaller than the symbol sizes.

Physical Properties of the Eclipsing Binary KIC 9851944: Asteroseismic Analysis

This paper is available on arxiv under CC 4.0 license.
Authors:
(1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk);
(2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK;
(3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia;
(4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. Table of Links Abstract and Intro
Observation
Orbital Ephemeris
Radial Velocity Analysis
Spectral Analysis
Analysis of the Light Curve
Physical Properties
Asteroseismic Analysis
Discussion
Conclusion, Data Availability, Acknowledgments, and References
Appendix A: Ephemeris Determination
Appendix B: Iteratively Prewhitened Frequencies
Appendix C: Detected Tidally Perturbed Pulsations 6 ANALYSIS OF THE LIGHT CURVE The components of KIC 9841944 are close to each other and thus have a significant tidal deformation. We therefore sought to model the light curve using a code that is based on Roche geometry. We selected the Wilson-Devinney (WD) code (Wilson & Devinney 1971; Wilson 1979) for this, and used the 2004 version of the code driven using the JKTWD wrapper (Southworth et al. 2011). The user guide which accompanies the WD code (Wilson & Van Hamme 2004) includes a description of all input and output quantities discussed below. The WD code is computationally expensive and is not suited to the analysis of the full 500 000 short-cadence datapoints in one step. We therefore used the orbital ephemeris determined in Section 3 to convert the datapoints to orbital phase, and then binned them into a much smaller number of points. We chose a bin size of 0.001 orbital phases during the eclipses and 0.005 outside the eclipses, resulting in a total of 456 phase-binned datapoints suitable for analysis with the WD code. Through a process of trying a large number of different fits with a range of fixed and fitted parameters, we arrived at a good solution to the light curve. We adopt this as the default solution, plot it in Fig. 9, and give the fitted parameters in Table 6. It was obtained in Mode = 0 with the following fitted parameters: the light contributions of the two stars; their potentials; their gravity darkening coefficients; the linear coefficients of the logarithmic LD law; and the orbital inclination. We fixed the mass ratio at the spectroscopic value, the orbital eccentricity to zero, the albedos to 1.1, the logarithmic coefficients of LD to values from Van Hamme (1993), third light to zero, and the rotation rates to synchronous. We adopted the maximum numerical precision values of N1 = N2 = 60 and N1L = N2L = 60, the simple treatment of reflection, and the Cousins R-band as a proxy for the Kepler passband. This solution gives a light ratio in excellent agreement with the spectroscopic values in Table 4. The fractional radii in Table 6 are volume-equivalent values calculated by the LC component of the WD code. For the determination of the uncertainties of the fitted parameters we ran a wide range of solutions with a large number of different possible approaches to modelling the light curve (see Southworth 2020). We calculated the errorbar for each parameter by adding in quadrature the contribution from every model choice, which in turn was taken to be the amount that parameter changed by versus the default solution. The following different approaches were explored. (i) We varied the amount of binning prior to the WD solution, finding that it had a negligible effect on the fitted parameters. (ii) We changed the numerical precision to N1 = N2 = N1L = N2L = 50. This modified the fractional radii by a maximum of 0.5%. (iii) We tried the detailed reflection effect and found almost identical results. (iv) Attempts to fit for mass ratio returned a value very close to the spectroscopic one and almost no change in the other parameters. (v) Fitting for the rotation rates of the stars yielded values close to and consistent with synchronous rotation and little change in the other parameters. (vi) Fitting for albedo gave a poorer fit but again very little change in the other parameters. (vii) Allowing for third light gave very similar parameters and a very small amount of third light consistent with zero. (viii) Fitting for one of the temperatures of the stars instead of the two light contributions directly (namely Mode = 2) changed the fractional radii by 0.2%. (ix) Fixing the limb darkening coefficients to theoretical values changed the fractional radii by 0.5%. (x) Using the square-root instead of logarithmic limb darkening law had a negligible effect. The best-fitting parameters were highly robust against all these experiments. The only significantly discrepant fit (neglecting our original exploratory ones) was when we used the Cousins I-band instead of the R-band. However, we are able to reject this fit as it is not consistent with the spectroscopic light ratio. The calculated uncertainties are given in Table 6. Fig. 9 shows that the best fit is extremely good, with an r.m.s. of 0.20 mmag, but that there are systematics remaining in the residuals. We attribute these to the WD numerical integration for points during the eclipses, and residual pulsations for points outside eclipse. Our approach of phase-binning the data gives a light curve practially without Poisson noise, so makes any imperfections in the fit easily noticable. We note that the systematics in the residuals of the fits we found to the data are too small to show up in plots of unbinned data, so may well be present in previous work on this object. This paper is available on arxiv under CC 4.0 license. Authors: (1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk); (2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK; (3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. This paper is available on arxiv under CC 4.0 license. Authors: Authors: (1) Z. Jennings, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK (E-mail: z.jennings@keele.ac.uk); (2) J. Southworth, Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK; (3) K. Pavlovski, Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia; (4) T. Van Reeth, Institute of Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium. Table of Links Abstract and Intro Observation Orbital Ephemeris Radial Velocity Analysis Spectral Analysis Analysis of the Light Curve Physical Properties Asteroseismic Analysis Discussion Conclusion, Data Availability, Acknowledgments, and References Appendix A: Ephemeris Determination Appendix B: Iteratively Prewhitened Frequencies Appendix C: Detected Tidally Perturbed Pulsations Abstract and Intro Abstract and Intro Observation Observation Orbital Ephemeris Orbital Ephemeris Radial Velocity Analysis Radial Velocity Analysis Spectral Analysis Spectral Analysis Analysis of the Light Curve Analysis of the Light Curve Physical Properties Physical Properties Asteroseismic Analysis Asteroseismic Analysis Discussion Discussion Conclusion, Data Availability, Acknowledgments, and References Conclusion, Data Availability, Acknowledgments, and References Appendix A: Ephemeris Determination Appendix A: Ephemeris Determination Appendix B: Iteratively Prewhitened Frequencies Appendix B: Iteratively Prewhitened Frequencies Appendix C: Detected Tidally Perturbed Pulsations Appendix C: Detected Tidally Perturbed Pulsations 6 ANALYSIS OF THE LIGHT CURVE The components of KIC 9841944 are close to each other and thus have a significant tidal deformation. We therefore sought to model the light curve using a code that is based on Roche geometry. We selected the Wilson-Devinney (WD) code (Wilson & Devinney 1971; Wilson 1979) for this, and used the 2004 version of the code driven using the JKTWD wrapper (Southworth et al. 2011). The user guide which accompanies the WD code (Wilson & Van Hamme 2004) includes a description of all input and output quantities discussed below. The WD code is computationally expensive and is not suited to the analysis of the full 500 000 short-cadence datapoints in one step. We therefore used the orbital ephemeris determined in Section 3 to convert the datapoints to orbital phase, and then binned them into a much smaller number of points. We chose a bin size of 0.001 orbital phases during the eclipses and 0.005 outside the eclipses, resulting in a total of 456 phase-binned datapoints suitable for analysis with the WD code. Through a process of trying a large number of different fits with a range of fixed and fitted parameters, we arrived at a good solution to the light curve. We adopt this as the default solution, plot it in Fig. 9, and give the fitted parameters in Table 6. It was obtained in Mode = 0 with the following fitted parameters: the light contributions of the two stars; their potentials; their gravity darkening coefficients; the linear coefficients of the logarithmic LD law; and the orbital inclination. We fixed the mass ratio at the spectroscopic value, the orbital eccentricity to zero, the albedos to 1.1, the logarithmic coefficients of LD to values from Van Hamme (1993), third light to zero, and the rotation rates to synchronous. We adopted the maximum numerical precision values of N1 = N2 = 60 and N1L = N2L = 60, the simple treatment of reflection, and the Cousins R-band as a proxy for the Kepler passband. This solution gives a light ratio in excellent agreement with the spectroscopic values in Table 4. The fractional radii in Table 6 are volume-equivalent values calculated by the LC component of the WD code. For the determination of the uncertainties of the fitted parameters we ran a wide range of solutions with a large number of different possible approaches to modelling the light curve (see Southworth 2020). We calculated the errorbar for each parameter by adding in quadrature the contribution from every model choice, which in turn was taken to be the amount that parameter changed by versus the default solution. The following different approaches were explored. (i) We varied the amount of binning prior to the WD solution, finding that it had a negligible effect on the fitted parameters. (ii) We changed the numerical precision to N1 = N2 = N1L = N2L = 50. This modified the fractional radii by a maximum of 0.5%. (iii) We tried the detailed reflection effect and found almost identical results. (iv) Attempts to fit for mass ratio returned a value very close to the spectroscopic one and almost no change in the other parameters. (v) Fitting for the rotation rates of the stars yielded values close to and consistent with synchronous rotation and little change in the other parameters. (vi) Fitting for albedo gave a poorer fit but again very little change in the other parameters. (vii) Allowing for third light gave very similar parameters and a very small amount of third light consistent with zero. (viii) Fitting for one of the temperatures of the stars instead of the two light contributions directly (namely Mode = 2) changed the fractional radii by 0.2%. (ix) Fixing the limb darkening coefficients to theoretical values changed the fractional radii by 0.5%. (x) Using the square-root instead of logarithmic limb darkening law had a negligible effect. The best-fitting parameters were highly robust against all these experiments. The only significantly discrepant fit (neglecting our original exploratory ones) was when we used the Cousins I -band instead of the R -band. However, we are able to reject this fit as it is not consistent with the spectroscopic light ratio. The calculated uncertainties are given in Table 6. I R Fig. 9 shows that the best fit is extremely good, with an r.m.s. of 0.20 mmag, but that there are systematics remaining in the residuals. We attribute these to the WD numerical integration for points during the eclipses, and residual pulsations for points outside eclipse. Our approach of phase-binning the data gives a light curve practially without Poisson noise, so makes any imperfections in the fit easily noticable. We note that the systematics in the residuals of the fits we found to the data are too small to show up in plots of unbinned data, so may well be present in previous work on this object.

Physical Properties of the Eclipsing Binary KIC 9851944: Analysis of the Light Curve

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