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1. New inflationary probes of axion dark matter

Author

Chen, Xingang, Fan, JiJi, and Li, Lingfeng

Subjects
High Energy Physics - Theory, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Cosmology and Nongalactic Astrophysics (astro-ph.CO), High Energy Physics - Theory (hep-th), FOS: Physical sciences, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

If a light axion is present during inflation and becomes part of dark matter afterwards, its quantum fluctuations contribute to dark matter isocurvature. In this article, we introduce a whole new suite of cosmological observables for axion isocurvature, which could help test the presence of axions, as well as its coupling to the inflaton and other heavy spectator fields during inflation such as the radial mode of the Peccei-Quinn field. They include correlated clock signals in the curvature and isocurvature spectra, and mixed cosmological-collider non-Gaussianities involving both curvature and isocurvature fluctuations with shapes and running unconstrained by the current data. Taking into account of the existing strong constraints on axion isocurvature fluctuations from the CMB, these novel signals could still be sizable and potentially observable. In some models, the signals, if observed, could even help us significantly narrow down the range of the inflationary Hubble scale, a crucial parameter difficult to be determined in general, independent of the tensor mode., Comment: 44 pages, 15 figures

Published
2023
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2. Early-Universe-Physics Insensitive and Uncalibrated Cosmic Standards: Constraints on $��_{\rm{m}}$ and Implications for the Hubble Tension

Author

Lin, Weikang, Chen, Xingang, and Mack, Katherine J.

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), High Energy Physics - Phenomenology (hep-ph), High Energy Physics - Theory (hep-th), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

To further shed light on whether pre-recombination models can resolve the Hubble tension, we explore constraints on the cosmic background evolution that are insensitive to early-universe physics. The analysis of the cosmic microwave background (CMB) anisotropy has been thought to highly rely on early-universe physics. However, we show that the fact that the sound horizon at recombination being close to that at the end of the drag epoch is insensitive to early-universe physics. This allows us to link the absolute sizes of the two horizons and treat them as free parameters. Jointly, the CMB peak angular size, Baryon Acoustic Oscillations (BAO), and Type Ia supernovae can be used as "early-universe-physics insensitive and uncalibrated cosmic standards", which measure the cosmic history from recombination to today. They can set strong and robust constraints on the post-recombination cosmic background, especially the matter density parameter with $��_{\rm{m}}=0.302\pm0.008$ ($68\%$ C.L.) assuming a flat $��$CDM after recombination. When we combine these with other non-local observations, we obtain several constraints on $H_0$ with significantly reduced sensitivity to early-universe physics. These are all more consistent with the Planck 2018 result than the local measurement results such as those based on Cepheids. This suggests a tension between the post-recombination, but non-local, observations and the local measurements which cannot be resolved by modifying pre-recombination early universe physics., Results updated with stellar-age constraints; conclusion unchanged. Accepted for publication in ApJ

Published
2021
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3. Quality Evaluation System of Oil-immersed Distribution Transformer Based on Big Data Technology

Author

Yingyue Zhu, Chen Shuting, Hui Zhu, Chen Xingang, Tan Yue, Yun Yuxin, and Chao Gu

Subjects
Relation (database), Computer science, business.industry, media_common.quotation_subject, Big data, Distribution transformer, Weighting, Reliability engineering, Electromagnetic coil, Entropy (information theory), Quality (business), business, Test data, media_common
Abstract

In order to better assess the health level of oil-immersed distribution transformers, the test data of the equipment in this paper was the entry point for quality assessment, and a more systematic quality assessment system for oil-immersed distribution transformers based on big data technology was constructed. The combined weighting of the order relation method and the entropy method was used to mine the test data of the oil-immersed distribution transformer, and the state parameters that can effectively characterize the quality of the oil-immersed distribution transformer was explored, combined with set pair analysis to build a multi-state variable-based distribution transformer quality evaluation model. The results show that the evaluation results of the system are basically consistent with the actual situation, indicating that the evaluation system has a certain effect on the quality evaluation of oil-immersed distribution transformers.

Published
2020
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4. Inflation and Dark Energy from spectroscopy at $z > 2$

Author

Ferraro, Simone, Wilson, Michael J, Abidi, Muntazir, Alonso, David, Ansarinejad, Behzad, Armstrong, Robert, Asorey, Jacobo, Avelino, Arturo, Baccigalupi, Carlo, Bandura, Kevin, Battaglia, Nicholas, Bavdhankar, Chetan, Bernal, José Luis, Beutler, Florian, Biagetti, Matteo, Blanc, Guillermo A, Blazek, Jonathan, Bolton, Adam S, Borrill, Julian, Frye, Brenda, Buckley-Geer, Elizabeth, Bull, Philip, Burgess, Cliff, Byrnes, Christian T, Cai, Zheng, Castander, Francisco J, Castorina, Emanuele, Chang, Tzu-Ching, Chaves-Montero, Jonás, Chen, Shi-Fan, Chen, Xingang, Balland, Christophe, Yèche, Christophe, Cohn, JD, Coulton, William, Courtois, Helene, Croft, Rupert AC, Cyr-Racine, Francis-Yan, D'Amico, Guido, Dawson, Kyle, Delabrouille, Jacques, Dey, Arjun, Doré, Olivier, Douglass, Kelly A, Yutong, Duan, Dvorkin, Cora, Eggemeier, Alexander, Eisenstein, Daniel, Fan, Xiaohui, Ferreira, Pedro G, Font-Ribera, Andreu, Foreman, Simon, García-Bellido, Juan, Gerbino, Martina, Gluscevic, Vera, Gontcho, Satya Gontcho A, Green, Daniel, Guy, Julien, Hahn, ChangHoon, Hanany, Shaul, Handley, Will, Hathi, Nimish, Hawken, Adam J, Hernández-Aguayo, César, Hložek, Renée, Huterer, Dragan, Ishak, Mustapha, Kamionkowski, Marc, Karagiannis, Dionysios, Keeley, Ryan E, Kehoe, Robert, Khatri, Rishi, Kim, Alex, Kneib, Jean-Paul, Kollmeier, Juna A, Kovetz, Ely D, Krause, Elisabeth, Krolewski, Alex, L'Huillier, Benjamin, Landriau, Martin, Levi, Michael, Liguori, Michele, Linder, Eric, Lukić, Zarija, Macorra, Axel de la, Plazas, Andrés A, Marshall, Jennifer L, Martini, Paul, Masui, Kiyoshi, McDonald, Patrick, Meerburg, P Daniel, Meyers, Joel, Mirbabayi, Mehrdad, Moustakas, John, Myers, Adam D, Palanque-Delabrouille, Nathalie, Newburgh, Laura, Newman, Jeffrey A, Niz, Gustavo, and Padmanabhan, Hamsa

Subjects
astro-ph.GA, astro-ph.CO, Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

The expansion of the Universe is understood to have accelerated during two epochs: in its very first moments during a period of Inflation and much more recently, at $z < 1$, when Dark Energy is hypothesized to drive cosmic acceleration. The undiscovered mechanisms behind these two epochs represent some of the most important open problems in fundamental physics. The large cosmological volume at $2 < z < 5$, together with the ability to efficiently target high-$z$ galaxies with known techniques, enables large gains in the study of Inflation and Dark Energy. A future spectroscopic survey can test the Gaussianity of the initial conditions up to a factor of ~50 better than our current bounds, crossing the crucial theoretical threshold of $\sigma(f_{NL}^{\rm local})$ of order unity that separates single field and multi-field models. Simultaneously, it can measure the fraction of Dark Energy at the percent level up to $z = 5$, thus serving as an unprecedented test of the standard model and opening up a tremendous discovery space.

Published
2019

5. Messengers from the Early Universe: Cosmic Neutrinos and Other Light Relics

Author

Green, Daniel, Amin, Mustafa A, Meyers, Joel, Wallisch, Benjamin, Abazajian, Kevork N, Abidi, Muntazir, Adshead, Peter, Ahmed, Zeeshan, Ansarinejad, Behzad, Armstrong, Robert, Baccigalupi, Carlo, Bandura, Kevin, Barron, Darcy, Battaglia, Nicholas, Baumann, Daniel, Bechtol, Keith, Bennett, Charles, Benson, Bradford, Beutler, Florian, Bischoff, Colin, Bleem, Lindsey, Bond, J Richard, Borrill, Julian, Buckley-Geer, Elizabeth, Burgess, Cliff, Carlstrom, John E, Castorina, Emanuele, Challinor, Anthony, Chen, Xingang, Cooray, Asantha, Coulton, William, Craig, Nathaniel, Crawford, Thomas, Cyr-Racine, Francis-Yan, D'Amico, Guido, Demarteau, Marcel, Doré, Olivier, Yutong, Duan, Dunkley, Joanna, Dvorkin, Cora, Ellison, John, Engelen, Alexander van, Escoffier, Stephanie, Essinger-Hileman, Tom, Fabbian, Giulio, Filippini, Jeffrey, Flauger, Raphael, Foreman, Simon, Fuller, George, Garcia, Marcos AG, García-Bellido, Juan, Gerbino, Martina, Gluscevic, Vera, Gontcho, Satya Gontcho A, Górski, Krzysztof M, Grin, Daniel, Grohs, Evan, Gudmundsson, Jon E, Hanany, Shaul, Handley, Will, Hill, J Colin, Hirata, Christopher M, Hložek, Renée, Holder, Gilbert, Horiuchi, Shunsaku, Huterer, Dragan, Kadota, Kenji, Kamionkowski, Marc, Keeley, Ryan E, Khatri, Rishi, Kisner, Theodore, Kneib, Jean-Paul, Knox, Lloyd, Koushiappas, Savvas M, Kovetz, Ely D, L'Huillier, Benjamin, Lahav, Ofer, Lattanzi, Massimiliano, Lee, Hayden, Liguori, Michele, Lin, Tongyan, Loverde, Marilena, Madhavacheril, Mathew, Masui, Kiyoshi, McMahon, Jeff, McQuinn, Matthew, Meerburg, P Daniel, Mirbabayi, Mehrdad, Motloch, Pavel, Mukherjee, Suvodip, Munõz, Julian B, Nagy, Johanna, Newburgh, Laura, Niemack, Michael D, Nomerotski, Andrei, Page, Lyman, Piacentni, Francesco, Pierpaoli, Elena, Pogosian, Levon, and Pryke, Clement

Subjects
High Energy Physics::Phenomenology, astro-ph.CO, hep-ph, Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

The hot dense environment of the early universe is known to have produced large numbers of baryons, photons, and neutrinos. These extreme conditions may have also produced other long-lived species, including new light particles (such as axions or sterile neutrinos) or gravitational waves. The gravitational effects of any such light relics can be observed through their unique imprint in the cosmic microwave background (CMB), the large-scale structure, and the primordial light element abundances, and are important in determining the initial conditions of the universe. We argue that future cosmological observations, in particular improved maps of the CMB on small angular scales, can be orders of magnitude more sensitive for probing the thermal history of the early universe than current experiments. These observations offer a unique and broad discovery space for new physics in the dark sector and beyond, even when its effects would not be visible in terrestrial experiments or in astrophysical environments. A detection of an excess light relic abundance would be a clear indication of new physics and would provide the first direct information about the universe between the times of reheating and neutrino decoupling one second later.

Published
2019

6. Primordial Non-Gaussianity

Author

Meerburg, P. Daniel, Green, Daniel, Abidi, Muntazir, Amin, Mustafa A., Adshead, Peter, Ahmed, Zeeshan, Alonso, David, Ansarinejad, Behzad, Armstrong, Robert, Avila, Santiago, Baccigalupi, Carlo, Baldauf, Tobias, Ballardini, Mario, Bandura, Kevin, Bartolo, Nicola, Battaglia, Nicholas, Baumann, Daniel, Bavdhankar, Chetan, Bernal, José Luis, Beutler, Florian, Biagetti, Matteo, Bischoff, Colin, Blazek, Jonathan, Bond, J. Richard, Borrill, Julian, Bouchet, François R., Bull, Philip, Burgess, Cliff, Byrnes, Christian, Calabrese, Erminia, Carlstrom, John E., Castorina, Emanuele, Challinor, Anthony, Chang, Tzu-Ching, Chaves-Montero, Jonás, Chen, Xingang, Yèche, Christophe, Cooray, Asantha, Coulton, William, Crawford, Thomas, Chisari, Elisa, Cyr-Racine, Francis-Yan, D Amico, Guido, Bernardis, Paolo, La Macorra, Axel, Doré, Olivier, Duivenvoorden, Adri, Dunkley, Joanna, Dvorkin, Cora, Eggemeier, Alexander, Escoffier, Stephanie, Essinger-Hileman, Tom, Fasiello, Matteo, Ferraro, Simone, Flauger, Raphael, Font-Ribera, Andreu, Foreman, Simon, Friedrich, Oliver, García-Bellido, Juan, Gerbino, Martina, Gluscevic, Vera, Goon, Garrett, Górski, Krzysztof M., Gudmundsson, Jon E., Gupta, Nikhel, Hanany, Shaul, Handley, Will, Hawken, Adam J., Hill, J. Colin, Hirata, Christopher M., Hložek, Renée, Holder, Gilbert, Huterer, Dragan, Kamionkowski, Marc, Kirit Karkare, Keeley, Ryan E., Kinney, William, Kisner, Theodore, Kneib, Jean-Paul, Knox, Lloyd, Koushiappas, Savvas M., Kovetz, Ely D., Koyama, Kazuya, L Huillier, Benjamin, Lahav, Ofer, Lattanzi, Massimiliano, Lee, Hayden, Liguori, Michele, Loverde, Marilena, Madhavacheril, Mathew, Maldacena, Juan, Marsh, M. C. David, Masui, Kiyoshi, Matarrese, Sabino, Mcallister, Liam, Mcmahon, Jeff, Mcquinn, Matthew, Meyers, Joel, Mirbabayi, Mehrdad, Moradinezhad Dizgah, Azadeh, Motloch, Pavel, Mukherjee, Suvodip, Muñoz, Julian B., Myers, Adam D., Nagy, Johanna, Naselsky, Pavel, Nati, Federico, Newburgh, Nicolis, Alberto, Niemack, Michael D., Niz, Gustavo, Nomerotski, Andrei, Page, Lyman, Pajer, Enrico, Padmanabhan, Hamsa, Palma, Gonzalo A., Peiris, Hiranya V., Percival, Will J., Piacentni, Francesco, Pimentel, Guilherme L., Pogosian, Levon, Prescod-Weinstein, Chanda, Pryke, Clement, Puglisi, Giuseppe, Racine, Benjamin, Stompor, Radek, Raveri, Marco, Remazeilles, Mathieu, Rocha, Graça, Ross, Ashley J., Rossi, Graziano, Ruhl, John, Sasaki, Misao, Schaan, Emmanuel, Schillaci, Alessandro, Schmittfull, Marcel, Sehgal, Neelima, Senatore, Leonardo, Seo, Hee-Jong, Shan, Huanyuan, Shandera, Sarah, Sherwin, Blake D., Silverstein, Eva, Simon, Sara, Slosar, Anze, Staggs, Suzanne, Starkman, Glenn, Stebbins, Albert, Suzuki, Aritoki, Switzer, Eric R., Timbie, Peter, Tolley, Andrew J., Tomasi, Maurizio, Tristram, Matthieu, Trodden, Mark, Tsai, Yu-Dai, Uhlemann, Cora, Umiltà, Caterina, Engelen, Alexander, Vargas-Magaña, M., Vieregg, Abigail, Wallisch, Benjamin, Wands, David, Wandelt, Benjamin, Wang, Yi, Watson, Scott, Wise, Mark, Wu, W. L. K., Xianyu, Zhong-Zhi, Xu, Weishuang, Yasini, Siavash, Young, Sam, Yutong, Duan, Zaldarriaga, Matias, Zemcov, Michael, Zhao, Gong-Bo, Zheng, Yi, and Zhu, Ningfeng

Subjects
High Energy Physics - Theory, Cosmology and Nongalactic Astrophysics (astro-ph.CO), High Energy Physics - Theory (hep-th), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Our current understanding of the Universe is established through the pristine measurements of structure in the cosmic microwave background (CMB) and the distribution and shapes of galaxies tracing the large scale structure (LSS) of the Universe. One key ingredient that underlies cosmological observables is that the field that sources the observed structure is assumed to be initially Gaussian with high precision. Nevertheless, a minimal deviation from Gaussianityis perhaps the most robust theoretical prediction of models that explain the observed Universe; itis necessarily present even in the simplest scenarios. In addition, most inflationary models produce far higher levels of non-Gaussianity. Since non-Gaussianity directly probes the dynamics in the early Universe, a detection would present a monumental discovery in cosmology, providing clues about physics at energy scales as high as the GUT scale., Comment: 5 pages + references; Submitted to the Astro2020 call for science white papers. This version: fixed author list

Published
2019
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7. A Temperature Monitoring System for SF6 Circuit Breaker Quenching Pot Based on Temperature Field Analysis

Author

Ma Jun, LI Changxin, and Chen Xingang

Subjects
Quenching, Materials science, Field (physics), Nuclear engineering, Heat transfer, High voltage, Surface acoustic wave sensor, computer.software_genre, computer, Circuit breaker, Finite element method, Simulation software
Abstract

Quenching pot’s temperature monitoring has been one of the most important problems in on-line monitoring of power equipment. A system of quenching pot of SF 6 circuit breaker temperature online monitoring is designed. According to the heat transfer theory, a mathematical model of quenching pot of high voltage circuit breaker is established. Having finite element calculation through COMSOL simulation software, the simulation results reflect the heat transfer law of each part of quenching pot and the temperature field distribution. Analyzing the characteristic of quenching pot temperature field gas flow field model. Using surface acoustic wave sensor to collect temperature, through the data processing module, sending the data to host computer’s interface, analyzing, displaying and storing the temperature data. Though the experimental test, the temperature monitoring system can meet the requirements of SF 6 circuit breaker quenching pot’s real-time monitoring.

Published
2018
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8. Multi-Objective Distribution Network Reconfiguration Based on Deep Learning Algorithm

Author

Chen Xiaoqing, Tan Hao, Yu Bing, Chen Xingang, and LI Changxin

Subjects
021103 operations research, Distribution networks, Computer science, business.industry, Deep learning, 0211 other engineering and technologies, Particle swarm optimization, Control reconfiguration, 020206 networking & telecommunications, 02 engineering and technology, AC power, Load balancing (computing), Convolutional neural network, Nonlinear system, 0202 electrical engineering, electronic engineering, information engineering, Artificial intelligence, business, Algorithm
Abstract

Distribution network reconfiguration is an important means to improve power supply reliability and reduce network loss. In this paper, a deep learning CNN (convolution neural network) model is established to solve the problem of switch status optimization under the constraints of distribution network operation. Deep learning is a branch of machine learning, for some complex issues, deep learning CNN can autonomously combine basic features into more complex features and learning the rules to solve practical problems. Firstly, a distribution network reconfiguration model with multi-objective as active power loss, average power supply availability indicator and load balancing indicator of the system is established. With the judgement matrix, the weight of each target is optimized according to the expert experience, and the multi-objective is transformed into a single-objective. Then, under different loads situation, the optimization model of single-objective distribution network reconfiguration model is solved by the particle swarm optimization algorithm to get the optimized switch open/closed combination. Taking the load of each node as input, the optimized switch open/closed combination is output, trained in deep learning CNN model, and the load characteristic is extracted by deep convolution neural network to simulate the nonlinear relationship of reconfiguration. The trained deep learning model can well simulate the switch status combinations under different loads and meet the requests of the optimization objective without Iteration and improve the reconfiguration efficiency in the actual distribution network.

Published
2018
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9. Fault detection of transformers based on Raman spectra of the dissolved gas in transformer oil

Author

Ma Zhipeng, Chen Xingang, and Yang Dingkun

Subjects
Voigt profile, Engineering, Transformer oil, business.industry, Dissolved gas analysis, Gaussian, 030231 tropical medicine, 020206 networking & telecommunications, 02 engineering and technology, Laser, Fault detection and isolation, law.invention, Computational physics, 03 medical and health sciences, symbols.namesake, 0302 clinical medicine, law, 0202 electrical engineering, electronic engineering, information engineering, Electronic engineering, symbols, Transformer, business, Raman spectroscopy
Abstract

Dissolved Gas Analysis (DGA) is one of the best way to monitor the running state of power transformers, but there are some defects of traditional DGA. Different from other DGA, Raman spectra gas detection technology using a single wavelength laser is able to detect dissolved gas in oil-immersed transformer without contact and loss, and it overcame the disadvantages of low accuracy and sensitivity of traditional DGA. With Gaussian View and Gaussian 09w simulation, the Raman spectra of 7 kinds of transformer fault gases have been obtained, and the Voigt function fitting has been made. The establishment of Raman spectroscopy detection platform aiming at analyzing the Raman spectra of fault gases has been completed in the laboratory, which accomplished the mission of improving the single gas Voigt function model of Raman spectra. Comparisons between the simulation values and the experimental values are made, and all the proofs tend that the synthesis data are in accord with the test data.

Published
2016
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10. In-in and $��N$ calculations of the bispectrum from non-attractor single-field inflation

Author

Chen, Xingang, Firouzjahi, Hassan, Komatsu, Eiichiro, Namjoo, Mohammad Hossein, and Sasaki, Misao

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), High Energy Physics - Theory (hep-th), FOS: Physical sciences
Abstract

In non-attractor single-field inflation models producing a scale-invariant power spectrum, the curvature perturbation on super-horizon scales grows as ${\cal R}\propto a^3$. This is so far the only known class of self-consistent single-field models with a Bunch-Davies initial state that can produce a large squeezed-limit bispectrum violating Maldacena's consistency relation. Given the importance of this result, we calculate the bispectrum with three different methods: using quantum field theory calculations in two different gauges, and classical calculations (the $��N$ formalism). All the results agree, giving the local-form bispectrum parameter of $f^{local}_{NL}=5(1+c_s^2)/(4c_s^2)$. This result is valid for arbitrary values of the speed of sound parameter, $c_s$, for a particular non-attractor model we consider in this paper., 19 pages, 3 figures

Published
2013
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11. Research of Infrared Diagnosed of Faults of Arrester

Author

Tian Xiaoxiao, Fan Li, and Chen Xingang

Subjects
Electric power system, Engineering, business.industry, Surge arrester, Overvoltage, Electrical engineering, Structural engineering, business, Fault (power engineering), Lightning arrester, human activities, Life testing, Voltage
Abstract

In order to analyze heat-characteristic in various fault of arrester, author using representational 6~10 kV and upward voltage grade of FZ, FCZ, MOA arrester and 110 kV arrester of four burl combination type which running in electric power system and wash out by preventive test, according to practicality running mode and equip homonymic eligibility element, arrester had been done broken-down simulate experimentation of bowel parallel resistance aging, humidify, parallel resistance rupture by 1.05~1.10 times rating voltage. At the same time contrast is testing result between infrared testing and general testing of DC leakage current, distributed voltage, and AC leakage current. Through the research of simulate experimentation for different fault of arrester, analyzed the heat-characteristic in different fault of arrester, then research and obtain the character of heat-image which in have and not fault of arrester, obtain some basic method to diagnosis and distinguish the fault of arrester. The result shows that heat of arrester mostly come of equal voltage badness of gaps of parallel resistance, and a number of heat-characteristic of vary arresters had been analyzed in order state and fault state, and gain some law of character of heat-image of arrester through simulate test and practice of locale detection.

Published
2008
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12. Inflationary trispectrum for models with large non-Gaussianities

Author

Chen, Xingang, Huang, Min-xin, and Shiu, Gary

Subjects
High Energy Physics - Theory, Physics, Inflation (cosmology), Nuclear and High Energy Physics, 010308 nuclear & particles physics, Astrophysics (astro-ph), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Inflaton, Astrophysics, 01 natural sciences, Cosmology, High Energy Physics - Phenomenology, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology (hep-ph), Classical mechanics, High Energy Physics - Theory (hep-th), 0103 physical sciences, C++ string handling, Inflationary epoch, Statistical physics, Trispectrum, Quantum field theory, 010303 astronomy & astrophysics, Bispectrum
Abstract

We compute the leading order contribution to the four-point function of the primordial curvature perturbation in a class of single field models where the inflationary Lagrangian is a general function of the inflaton and its first derivative. This class of models includes string motivated inflationary models such as DBI inflation. We find that the trispectrum for some range of parameters could potentially be observed in future experiments. Moreover, the trispectrum can distinguish DBI inflation from other inflation models with large non-Gaussianities which typically have a similar bispectrum. We also derive a set of consistency conditions for n-point functions of the primordial curvature perturbation in single field inflation, generalizing Maldacena's result for 3-point functions., v2: 5 pages, journal version. v3, v4: formulae for the momentum dependence of trispectrum corrected, main conclusions remain unchanged, this version supersedes the journal version. v5: minor revision with an added reference

Published
2006
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13. A new approach to determine parameters of synchronous machine using wavelet transform and Prony algorithm

Author

Wu Xusheng, Chen Xingang, Yang Kaisheng, Wang Zhifei, and Ji Luming

Subjects
Discrete wavelet transform, Wavelet, Stationary wavelet transform, Second-generation wavelet transform, Wavelet transform, Cascade algorithm, Harmonic wavelet transform, Algorithm, Mathematics, Wavelet packet decomposition
Abstract

Based on the wavelet transform and the Prony algorithm, a new method is presented to determine parameters of synchronous machine from sudden balanced short-circuit test. An appropriate wavelet function is chosen to analyze the sudden balance short-circuit transient current and the DC and fundamental component of the transient short-circuit currents are obtained by the wavelet transform. Compared with the traditional methods, the analysis using wavelet transform is more effective. Thus, the precise transient parameters and aperiodic component time constant are estimated by the least square algorithm. Meanwhile, the precise subtransient parameters are estimated through the Prony algorithm. At last, the test of sudden balanced short-circuit are carried out in a three-phase synchronous machine. The test results show that the method developed in this paper is valid.

Published
2005
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14. Astro2020 Science White Paper: Cosmological Synergies Enabled by Joint Analysis of Multi-probe data from WFIRST, Euclid, and LSST

Author

Rhodes, Jason, Alonso, David, Ansarinejad, Behzad, Armstrong, Robert, Asorey, Jacobo, Avelino, Arturo, Blazek, Jonathan, Castander, Francisco J., Chary, Ranga Ram, Chen, Xingang, Choi, Ami, Clowe, Douglas, Cohen-Tanugi, Johann, Comparat, Johan, Croft, Rupert A. C., Doré, Olivier, Escoffier, Stephanie, Foley, Ryan, Fosalba, Pablo, Gruen, Daniel, Gupta, Nikhel, Guzzo, Luigi, Hawken, Adam J., Hemmati, Shoubaneh, Heitmann, Katrin, Hernquist, Lars, Heymans, Catherine, Hirata, Christopher M., Hoekstra, Henk, Huterer, Dragan, Iliev, Ilian T., Jain, Bhuvnesh, Jha, Saurabh W., Keeley, Ryan E., Kiessling, Alina, Kitching, Thomas, Koekemoer, Anton, Koushiappas, Savvas M., Kovetz, Ely D., Kruk, Jeff, L Huillier, Benjamin, Lahav, Ofer, Pablo Lemos, La Macorra, Axel, Plazas Malagón, Andrés, Mandelbaum, Rachel, Masters, Daniel, Mcquinn, Matthew, Melchior, Peter, Miyatake, Hironao, Newman, Jeffrey A., Nichol, Robert, Niz, Gustavo, O Connor, Paul, Penna-Lima, Mariana, Percival, Will J., Perlmutter, Saul, Pisani, Alice, Rigault, Mickael, Rossi, Graziano, Schmittfull, Marcel, Schuhmann, Robert, Scolnic, Dan, Sereno, Mauro, Shan, Huanyuan, Shirasaki, Masato, Simon, Sara, Slosar, Anže, Spergel, David, Sridhar, Srivatsan, Takada, Masahiro, Troxel, M. A., Wang, Yun, Weinberg, David, Yoshida, Naoki, Zhang, Yuanyuan, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Durham University, Lawrence Livermore National Laboratory (LLNL), Korea Astronomy and Space Science Institute (KASI), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Ecole Polytechnique Fédérale de Lausanne (EPFL), Institut de Ciencies de l'Espai [Barcelona] (ICE-CSIC), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Infrared Processing and Analysis Center (IPAC), California Institute of Technology (CALTECH), Ohio State University [Columbus] (OSU), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, Carnegie Mellon University [Pittsburgh] (CMU), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), University of California [Santa Cruz] (UC Santa Cruz), University of California (UC), Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), Stanford University, University of Melbourne, Dipartimento di Fisica (Milano), Università degli Studi di Milano = University of Milan (UNIMI), Argonne National Laboratory [Lemont] (ANL), Royal Observatory Edinburgh (ROE), University of Edinburgh, Leiden Observatory [Leiden], Universiteit Leiden, University of Sussex, University of Pennsylvania, Mullard Space Science Laboratory (MSSL), University College of London [London] (UCL), Space Telescope Science Institute (STSci), Brown University, Ben-Gurion University of the Negev (BGU), NASA Goddard Space Flight Center (GSFC), Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), Princeton University, Nagoya University, Department of Physics and Astronomy [Pittsburgh], University of Pittsburgh (PITT), Pennsylvania Commonwealth System of Higher Education (PCSHE)-Pennsylvania Commonwealth System of Higher Education (PCSHE), University of Portsmouth, Universidad de Guanajuato, Brookhaven National Laboratory [Upton, NY] (BNL), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE), Universidade de Brasilia [Brasília] (UnB), University of Waterloo [Waterloo], Perimeter Institute for Theoretical Physics [Waterloo], Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy and Space Science [Sejong University], Sejong University, Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Duke University [Durham], Dipartimento di Fisica, Politecnico di Torino = Polytechnic of Turin (Polito), Shanghai Astronomical Observatory [Shanghai] (SHAO), Chinese Academy of Sciences [Beijing] (CAS), National Astronomical Observatory of Japan (NAOJ), Flatiron Institute, Simons Foundation, Korea Internet Security Agency (KISA), Institute for the Physics and Mathematics of the Universe (IPMU), The University of Tokyo (UTokyo), Fermilab Center for Particle Astrophysics, Fermi National Accelerator Laboratory (Fermilab), Okayama University, Smithsonian Institution-Harvard University [Cambridge], Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), University of California [Santa Cruz] (UCSC), University of California, Università degli Studi di Milano [Milano] (UNIMI), Universiteit Leiden [Leiden], University of Pennsylvania [Philadelphia], Universidad Nacional Autónoma de México (UNAM), U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), and HEP, INSPIRE

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.GRQC] Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], [PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience; NASA, NSF, and DOE will collectively spend well over $4B this decade and the next on missions and surveys that have dark energy cosmology as one of their primary drivers. WFIRST, Euclid, and LSST are all missions designed to perform dedicated surveys that offer unprecedented statistical constraining power and control of systematic uncertainties. However, there is a growing realization that these missions will be significantly more powerful when the data are processed and analyzed in unison. This will require coordinated cross-survey and interagency effort. With proper attention to how data are jointly processed and analyzed, the combination of these missions will provide constraints and systematics control that is better than the sum of their individual parts, as stated in the title of Jain, et al. (2015). We advocate for the three relevant US agencies to work together with our international partners to ensure that the synergy from these multi-probe missions is fully realized.

15. The Origin of the Universe as Revealed Through the Polarization of the Cosmic Microwave Background

Author

Dodelson, Scott, Easther, Richard, Hanany, Shaul, Mcallister, Liam, Meyer, Stephan, Page, Lyman, Ade, Peter, Amblard, Alexandre, Ashoorioon, Amjad, Baccigalupi, Carlo, Balbi, Amedeo, Bartlett, James, Bartolo, Nicola, Baumann, Daniel, Beltran, Maria, Benford, Dominic, Birkinshaw, Mark, Bock, Jamie, Bond, Dick, Borrill, Julian, Bouchet, Francois, Bridges, Michael, Bunn, Emory, Calabrese, Erminia, Cantalupo, Christopher, Caramete, Ana, Carbone, Carmelita, Carroll, Sean, Chatterjee, Suchetana, Chen, Xingang, Church, Sarah, Chuss, David, Contaldi, Carlo R., Cooray, Asantha R., Creminelli, Paolo, Das, Sudeep, Bernardis, Francesco, Bernardis, Paolo, Delabrouille, Jacques, Desert, F. Xavier, Devlin, Mark J., Dickinson, Clive, Dicker, Simon, Dipirro, Michael, Dobbs, Matt A., Dore, Olivier, Dotson, Jessie, Dunkley, Joanna, Dvorkin, Cora, Eriksen, H. K., Falvella, Maria Cristina, Finley, Dave, Finkbeiner, Douglas P., Fixsen, Dale, Flauger, Raphael, Fosalba, Pablo, Fowler, Joseph W., Galli, Silvia, Gates, Evalyn I., Gear, Walter, Giraud-Heraud, Yannick, Gorski, Krzysztof, Greene, Brian, Gruppuso, Alessandro, Gundersen, Joshua, Halpern, Mark, Hamilton, Jean-Christophe, Hazumi, Masashi, Hernandez-Monteagudo, Carlos, Hertzberg, Mark, Hinshaw, Gary, Hirata, Christopher, Hivon, Eric, Holman, Richard, Holmes, Warren, Hu, Wayne, Hubmayr, Johannes, Huffenberger, Kevin, Hui, Howard, Hui, Lam, Irwin, Kent, Jackson, Mark, Jaffe, Andrew H., Johnson, Bradley, Johnson, Dean, Jones, William, Kachru, Shamit, Kadota, Kenji, Kaplan, Jean, Kaplinghat, Manoj, Keating, Brian G., Keskitalo, Reijo, Khoury, Justin, Kinney, William H., Kisner, Theodore, Knox, Lloyd, Kodama, Hideo, Kogut, Alan, Komatsu, Eiichiro, Kosowsky, Arthur, Kovac, John, Krauss, Lawrence M., Kurki-Suonio, Hannu, Lamarre, Jean-Michel, Landau, Susana Judith, Lawrence, Charles, Leach, Samuel M., Leblond, Louis, Lee, Adrian, Leitch, Erik, Leonardi, Rodrigo, Lesgourgues, Julien, Liddle, Andrew R., Lim, Eugene A., Limon, Michele, Loverde, Marilena, Lubin, Philip, Lunghi, Enrico, Lykken, Joseph D., Mactavish, Carolyn, Magalhaes, Antonio, Maino, Davide, Martin, Victoria, Sabino Matarrese, Mather, John C., Mathur, Harsh, Matsumura, Tomotake, Meerburg, Pieter, Melchiorri, Alessandro, Mersini-Houghton, Laura, Miller, Amber, Milligan, Michael, Moodley, Kavilan, Neimack, Michael, Nguyen, Hogan, Nicolis, Alberto, O Dwyer, Ian, Olinto, Angela, Pagano, Luca, Pajer, Enrico, Partridge, Bruce, Pearson, Timothy, Peiris, Hiranya V., Peloso, Marco, Piacentini, Francesco, Piat, Michel, Piccirillo, Lucio, Pierpaoli, Elena, Pietrobon, Davide, Pisano, Giampaolo, Pogosian, Levon, Pogosyan, Dmitri, Ponthieu, Nicolas, Popa, Lucia, Pryke, Clement, Raeth, Christoph, Ray, Subharthi, Reichardt, Christian, Ricciardi, Sara, Richards, Paul, Riotto, Antonio, Rocha, Graca, Ruhl, John, Rusholme, Benjamin, Scherrer, Robert, Scoccola, Claudia, Scott, Douglas, Sealfon, Carolyn, Sefusatti, Emiliano, Sehgal, Neelima, Seiffert, Michael, Senatore, Leonardo, Serra, Paolo, Shandera, Sarah E., Shimon, Meir, Shirron, Peter, Sievers, Jonathan, Silk, Joseph I., Sigurdson, Kris, Silverberg, Robert F., Silverstein, Eva, Staggs, Suzanne, Starkman, Glenn D., Stebbins, Albert, Stivoli, Federico, Stompor, Radek, Sugiyama, Naoshi, Swetz, Daniel, Tartari, Andrea, Tegmark, Max, Timbie, Peter, Titov, Maxim P., Tristram, Matthieu, Trodden, Mark, Tucker, Gregory, Urrestilla, Jon, Veneziani, Marcella, Verde, Licia, Vieira, Joaquin, Walker, Terry, Wands, David, Watson, Scott, Weinberg, Steven, Weiss, Rainer, Wandelt, Benjamin, Winstein, Bruce D., Wollack, Edward, Wyman, Mark, Yadav, Amit, Yoon, Ki Won, Zahn, Olivier, Zaldarriaga, Matias, Zemcov, Michael, Zwart, Jonathan, APC - Cosmologie, AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), APC - Gravitation (APC-Gravitation), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Max-Planck-Gesellschaft-Max-Planck-Gesellschaft, APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Bartlett, James, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Max-Planck-Institut für Gravitationsphysik ( Albert-Einstein-Institut ) (AEI), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, and Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO)

Subjects
[SDU.ASTR.CO] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astrophysics::Cosmology and Extragalactic Astrophysics
Abstract

Modern cosmology has sharpened questions posed for millennia about the origin of our cosmic habitat. The age-old questions have been transformed into two pressing issues primed for attack in the coming decade: How did the Universe begin? and What physical laws govern the Universe at the highest energies? The clearest window onto these questions is the pattern of polarization in the Cosmic Microwave Background (CMB), which is uniquely sensitive to primordial gravity waves. A detection of the special pattern produced by gravity waves would be not only an unprecedented discovery, but also a direct probe of physics at the earliest observable instants of our Universe. Experiments which map CMB polarization over the coming decade will lead us on our first steps towards answering these age-old questions.

16. Inflation: Theory and Observations

Author

Achúcarro, Ana, Biagetti, Matteo, Matteo Braglia, Cabass, Giovanni, Caldwell, Robert, Castorina, Emanuele, Chen, Xingang, Coulton, William, Flauger, Raphael, Fumagalli, Jacopo, Ivanov, Mikhail M., Lee, Hayden, Maleknejad, Azadeh, Meerburg, P. Daniel, Dizgah, Azadeh Moradinezhad, Palma, Gonzalo A., Pimentel, Guilherme L., Renaux-Petel, Sébastien, Wallisch, Benjamin, Wandelt, Benjamin D., Witkowski, Lukas T., and Wu, W. L. Kimmy

Subjects
High Energy Physics - Theory, Astrophysics and Astronomy, Cosmology and Nongalactic Astrophysics (astro-ph.CO), hep-th, FOS: Physical sciences, hep-ph, Astrophysics::Cosmology and Extragalactic Astrophysics, High Energy Physics - Phenomenology, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology (hep-ph), High Energy Physics - Theory (hep-th), astro-ph.CO, Particle Physics - Theory, Astrophysics - Cosmology and Nongalactic Astrophysics, Particle Physics - Phenomenology
Abstract

Cosmic inflation provides a window to the highest energy densities accessible in nature, far beyond those achievable in any realistic terrestrial experiment. Theoretical insights into the inflationary era and its observational probes may therefore shed unique light on the physical laws underlying our universe. This white paper describes our current theoretical understanding of the inflationary era, with a focus on the statistical properties of primordial fluctuations. In particular, we survey observational targets for three important signatures of inflation: primordial gravitational waves, primordial non-Gaussianity and primordial features. With the requisite advancements in analysis techniques, the tremendous increase in the raw sensitivities of upcoming and planned surveys will translate to leaps in our understanding of the inflationary paradigm and could open new frontiers for cosmology and particle physics. The combination of future theoretical and observational developments therefore offer the potential for a dramatic discovery about the nature of cosmic acceleration in the very early universe and physics on the smallest scales., Contribution to Snowmass 2021; 103 pages, 8 figures, 378 endorsers; v2: minor changes

17. Messengers from the Early Universe: Cosmic Neutrinos and Other Light Relics

Author

Green, Daniel, Amin, Mustafa A., Meyers, Joel, Wallisch, Benjamin, Abazajian, Kevork N., Abidi, Muntazir, Adshead, Peter, Ahmed, Zeeshan, Ansarinejad, Behzad, Armstrong, Robert, Baccigalupi, Carlo, Bandura, Kevin, Barron, Darcy, Battaglia, Nicholas, Baumann, Daniel, Bechtol, Keith, Bennett, Charles, Benson, Bradford, Beutler, Florian, Bischoff, Colin, Bleem, Lindsey, Richard Bond, J., Borrill, Julian, Buckley-Geer, Elizabeth, Burgess, Cliff, Carlstrom, John E., Castorina, Emanuele, Challinor, Anthony, Chen, Xingang, Cooray, Asantha, Coulton, William, Craig, Nathaniel, Crawford, Thomas, Cyr-Racine, Francis-Yan, D Amico, Guido, Demarteau, Marcel, Doré, Olivier, Yutong, Duan, Dunkley, Joanna, Dvorkin, Cora, Ellison, John, Engelen, Alexander, Escoffier, Stephanie, Essinger-Hileman, Tom, Fabbian, Giulio, Filippini, Jeffrey, Flauger, Raphael, Foreman, Simon, Fuller, George, Garcia, Marcos A. G., García-Bellido, Juan, Gerbino, Martina, Gluscevic, Vera, Gontcho A Gontcho, Satya, Górski, Krzysztof M., Grin, Daniel, Grohs, Evan, Gudmundsson, Jon E., Hanany, Shaul, Handley, Will, Colin Hill, J., Hirata, Christopher M., Hložek, Renée, Holder, Gilbert, Horiuchi, Shunsaku, Huterer, Dragan, Kadota, Kenji, Kamionkowski, Marc, Keeley, Ryan E., Khatri, Rishi, Kisner, Theodore, Kneib, Jean-Paul, Knox, Lloyd, Koushiappas, Savvas M., Kovetz, Ely D., L Huillier, Benjamin, Lahav, Ofer, Lattanzi, Massimiliano, Lee, Hayden, Liguori, Michele, Lin, Tongyan, Loverde, Marilena, Madhavacheril, Mathew, Masui, Kiyoshi, Mcmahon, Jeff, Mcquinn, Matthew, Daniel Meerburg, P., Mirbabayi, Mehrdad, Motloch, Pavel, Mukherjee, Suvodip, Munõz, Julian B., Nagy, Johanna, Newburgh, Laura, Niemack, Michael D., Nomerotski, Andrei, Page, Lyman, Piacentni, Francesco, Pierpaoli, Elena, Pogosian, Levon, Pryke, Clement, Puglisi, Giuseppe, Stompor, Radek, Raveri, Marco, Reichardt, Christian L., Rose, Benjamin, Rossi, Graziano, Ruhl, John, Schaan, Emmanuel, Schubnell, Michael, Schutz, Katelin, Sehgal, Neelima, Senatore, Leonardo, Seo, Hee-Jong, Sherwin, Blake D., Simon, Sara, Slosar, Anže, Staggs, Suzanne, Albert Stebbins, Suzuki, Aritoki, Switzer, Eric R., Timbie, Peter, Tristram, Matthieu, Trodden, Mark, Tsai, Yu-Dai, Umiltà, Caterina, Di Valentino, Eleonora, Vargas-Magaña, M., Vieregg, Abigail, Watson, Scott, Weiler, Thomas, Whitehorn, Nathan, Wu, W. L. K., Xu, Weishuang, Xu, Zhilei, Yasini, Siavash, Zaldarriaga, Matias, Zhao, Gong-Bo, Zhu, Ningfeng, Zuntz, Joe, Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire de l'Accélérateur Linéaire (LAL), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Aix Marseille Université (AMU), Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), and HEP, INSPIRE

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), long-lived, gravitation: effect, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, cosmic background radiation, High Energy Physics - Phenomenology (hep-ph), time: reheating, relic density, new physics, High Energy Physics::Phenomenology, photon, gravitational radiation, hep-ph, neutrino: sterile, boundary condition, [PHYS.HPHE] Physics [physics]/High Energy Physics - Phenomenology [hep-ph], High Energy Physics - Phenomenology, gravitational radiation: emission, axion, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], astro-ph.CO, [PHYS.ASTR] Physics [physics]/Astrophysics [astro-ph], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], neutrino: decoupling, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The hot dense environment of the early universe is known to have produced large numbers of baryons, photons, and neutrinos. These extreme conditions may have also produced other long-lived species, including new light particles (such as axions or sterile neutrinos) or gravitational waves. The gravitational effects of any such light relics can be observed through their unique imprint in the cosmic microwave background (CMB), the large-scale structure, and the primordial light element abundances, and are important in determining the initial conditions of the universe. We argue that future cosmological observations, in particular improved maps of the CMB on small angular scales, can be orders of magnitude more sensitive for probing the thermal history of the early universe than current experiments. These observations offer a unique and broad discovery space for new physics in the dark sector and beyond, even when its effects would not be visible in terrestrial experiments or in astrophysical environments. A detection of an excess light relic abundance would be a clear indication of new physics and would provide the first direct information about the universe between the times of reheating and neutrino decoupling one second later., 5 pages + references; 1 figure; science white paper submitted to the Astro2020 decadal survey

18. Snowmass Theory Frontier: Astrophysics and Cosmology

Author

Green, Daniel, Ruderman, Joshua T., Safdi, Benjamin R., Shelton, Jessie, Achucarro, Ana, Adshead, Peter, Akrami, Yashar, Baryakhtar, Masha, Baumann, Daniel, Berlin, Asher, Blinov, Nikita, Boddy, Kimberly K., Buschmann, Malte, Cabass, Giovanni, Caldwell, Robert, Castorina, Emanuele, Chen, Thomas Y., Chen, Xingang, Coulton, William, Croon, Djuna, Yanou Cui, Curtin, David, Cyr-Racine, Francis-Yan, Dessert, Christopher, Dienes, Keith R., Draper, Patrick, Du, Peizhi, Ellis, Sebastian A. R., Essig, Rouven, Flauger, Raphael, Fong, Chee Sheng, Foster, Joshua W., Fumagalli, Jacopo, Harigaya, Keisuke, Horiuchi, Shunsaku, Ivanov, Mikhail M., Kahn, Yonatan, Knapen, Simon, Leane, Rebecca K., Lee, Hayden, Lentz, Erik W., Lewandowski, Matthew, Lisanti, Mariangela, Long, Andrew J., Loverde, Marilena, Maleknejad, Azadeh, Mcallister, Liam, Mcdermott, Samuel D., Mcgehee, Robert, Meerburg, P. Daniel, Meyers, Joel, Dizgah, Azadeh Moradinezhad, Münchmeyer, Moritz, Outmezguine, Nadav Joseph, Pajer, Enrico, Palma, Gonzalo A., Parikh, Aditya, Park, Jong-Chul, Peter, Annika H. G., Pimentel, Guilherme L., Renaux-Petel, Sébastien, Rodd, Nicholas L., Shakya, Bibhushan, Shiu, Gary, Silverstein, Eva, Simonovic, Marko, Singh, Rajeev, Sleight, Charlotte, Takhistov, Volodymyr, Tanedo, Philip, Taronna, Massimo, Thomas, Brooks, Toro, Natalia, Tsai, Yu-Dai, Vitagliano, Edoardo, Vogelsberger, Mark, Wallisch, Benjamin, Wandelt, Benjamin D., Wechsler, Risa H., Weniger, Christoph, Wu, W. L. Kimmy, Xu, Weishuang Linda, Yamada, Masaki, Yu, Hai-Bo, Zhang, Zhengkang, Zhong, Yi-Ming, and Zurek, Kathryn

Subjects
High Energy Physics - Theory, High Energy Physics - Phenomenology, Astrophysics and Astronomy, High Energy Physics - Phenomenology (hep-ph), Cosmology and Nongalactic Astrophysics (astro-ph.CO), High Energy Physics - Theory (hep-th), hep-th, astro-ph.CO, FOS: Physical sciences, hep-ph, Particle Physics - Theory, Astrophysics - Cosmology and Nongalactic Astrophysics, Particle Physics - Phenomenology
Abstract

We summarize progress made in theoretical astrophysics and cosmology over the past decade and areas of interest for the coming decade. This Report is prepared as the TF09 "Astrophysics and Cosmology" topical group summary for the Theory Frontier as part of the Snowmass 2021 process., Comment: 57 pages

19. Questions on calculation of primordial power spectrum with large spikes: the resonance model case

Author

Inomata, Keisuke, Braglia, Matteo, Chen, Xingang, and Renaux-Petel, Sébastien

Subjects
High Energy Physics - Phenomenology, Cosmology and Nongalactic Astrophysics (astro-ph.CO), High Energy Physics - Phenomenology (hep-ph), FOS: Physical sciences, Astronomy and Astrophysics, General Relativity and Quantum Cosmology (gr-qc), General Relativity and Quantum Cosmology, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Inflationary models predicting a scale-dependent large amplification of the density perturbations have recently attracted a lot of attention because the amplified perturbations can seed a sizable amount of primordial black holes (PBHs) and stochastic background of gravitational waves (GWs). While the power spectra in these models are computed based on the linear equation of motion, it is not obvious whether loop corrections are negligible when such a large amplification occurs during inflation. In this paper, as a first step to discuss the loop corrections in such models, we use the in-in formalism and calculate the one-loop scalar power spectrum numerically and analytically in an illustrative model where the density perturbations are resonantly amplified due to oscillatory features in the inflaton potential. Our calculation is technically new in that the amplified perturbations are numerically taken into account in the in-in formalism for the first time. In arriving at our analytical estimates, we highlight the role that the Wronskian condition of perturbations, automatically satisfied in our model, plays in obtaining the correct estimates. We also discuss the necessary conditions for subdominant loop corrections in this model. We find that, for the typical parameter space leading to the $\mathcal O(10^7)$ amplification of the power spectrum required for a sufficient PBH production, the one-loop power spectrum dominates over the tree-level one, indicating the breakdown of the perturbation theory., Comment: 42 pages, 14 figures, v3: An error in the equation of the two-vertex contribution corrected. Accordingly, the splitting of the two-vertex contribution changed and Appendix B added. The final one-loop power spectrum becomes smaller than the previous results, whereas the main conclusion (the typical oscillatory models lead to dominant loop power spectra) is unchanged

20. Satellite observations of level 2 products over the Amazon rainforest during the August 15th-22nd fires from TROPOMI

Author

Cahlon, Schlomo T. Z., Chance, Kelly, González Abad, Gonzalo, Chen, Xingang, and Gordon, Iouli

Subjects
TROPOMI (TROPOspheric Monitoring Instrument), Astro 98, Amazon Rainforest
Abstract

The TROPOMI (TROPOspheric Monitoring Instrument) is on board the Copernicus Sentinel 5 Precursor (S5P) satellite. TROPOMI level 2 data products are generated within the Copernicus ground system. The date products contain information on the data quality for each TROPOMI ground pixel. We present data on the variations of levels of aerosol layer height (ALH), carbon monoxide (CO), formaldehyde (HCHO), methane (CH4), nitrogen dioxide (NO2), total ozone column (O3), and sulphur dioxide (SO2) over the Amazon Rainforests before, during, and after the fires., Astro 98, {"references":["Chance, K., Palmer, P., Spurr, R., Martin, R., Kurosu, T., & Jacob, D. (2000). Satellite observations of formaldehyde over North America from GOME. Geophysical Research Letters, 27(21), 3461-3464. Heikkilä, A., Lakkala, K., Mielonen, T., Tamminen, J. (2018). The TROPOMI surface UV algorithm. Atmospheric Measurement Techniques, 11(2), 997-1008.","Heilig, G. (1994). The greenhouse gas methane (CH4): Sources and sinks, the impact of population growth, possible interventions. Population and Environment, 16(2), 109-137.","J Geophys Res Atmos, 106 (D13) (2001), pp. 14539-14550.","Le Quere, C., Andrew, Friedlingstein, Sitch, Pongratz, Manning, . . . Oak Ridge National Lab. (2018). Global Carbon Budget 2017. Earth System Science Data (Online), 10(1), 405-448. Lindfors, A., Kujanpää, J., Kalakoski, N.,","Nepstad, D. \"An Interview with Earth Innovation Founder, Dan Nepstad\". (2019). Environmental Progress. Link:http://environmentalprogress .org/big-news/2019/8/29/an7 interview-with-founder-of-earthinnovation- dan-nepstad","Palmer, Paul I., Daniel J. Jacob, Kelly Chance, Randall V. Martin, Robert J. D. Spurr, Thomas P. Kurosu, Isabelle Bey, Robert Yantosca, Arlene Fiore, and Qinbin Li. 2001. \"Air Mass Factor Formulation for Spectroscopic Measurements from Satellites: Application to Formaldehyde Retrievals from the Global Ozone Monitoring Experiment.\" Journal of Geophysical Research 106 (D13): 14539. doi:10.1029/2000jd900772","Park, R., Jeong, J., Lee, S., Kurosu, T., Palmer, P., & Chance, K. (2017). Sensitivity of formaldehyde (HCHO) column measurements from a geostationary satellite to temporal variation of the air mass factor in East Asia. Atmospheric Chemistry and Physics, 17(7), 4673-4686.","Pierre-Louis, K. The Amazon, Siberia, Indonesia: A World of Fire. (2019). International New York Times, p. International New York Times, August 30, 2019.","Reisen, F., Meyer, C., Mccaw, L., Powell, J., Tolhurst, K., Keywood, M., & Gras, J. (2011). Impact of smoke from biomass burning on air quality in rural communities in southern Australia. Atmospheric Environment, 45(24), 3944-3953.","Urbanski, S. (2014). Wildland fire emissions, carbon, and climate: Emission factors. Forest Ecology and Management, 317(C), 51-60.","van der Werf, G. R., Randerson, J. T., Giglio, L., Collatz, G. J., Mu, M., Kasibhatla, P. S., Morton, D. C., DeFries, R. S., Jin, Y., and van Leeuwen, T. T.: Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997– 2009), Atmos. Chem. Phys., 10, 11707–11735, doi:10.5194/acp10- 11707-2010, 2010.","Voiland, A. (2019). \"Uptick in Amazon Fire Activity in 2019\". NASA Earth Observatory. Link: https://earthobservatory.nasa.gov /images/145498/uptick-inamazon- fire-activity-in-2019","Wang, T., Wang, P., Theys, N., Tong, D., Hendrick, F., Zhang, Q., and Van Roozendael, M.: Spatial and temporal changes in SO2 regimes over China in the recent decade and the driving mechanism, Atmos. Chem. Phys., 18, 18063–18078, https://doi.org/10.5194/acp-18- 18063-2018, 2018."]}

Published
2020
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