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Detectability of neutrino-signal fluctuations induced by the hadron-quark phase transition in failing core-collapse supernovae

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Physical Review D 2024年第2期109卷 023005-023005页

作者： Zidu Lin Shuai Zha Evan P. O’Connor Andrew W. Steiner Department of Physics and Astronomy University of Tennessee Knoxville Knoxville 37996 USA Tsung-Dao Lee Institute Shanghai Jiao Tong University Shanghai 200240 China Yunnan Observatories Chinese Academy of Sciences (CAS) Kunming 650216 China Key Laboratory for the Structure and Evolution of Celestial Objects CAS Kunming 650216 China International Centre of Supernovae Yunnan Key Laboratory Kunming 650216 China The Oskar Klein Centre Department of Astronomy Stockholm University AlbaNova SE-106 91 Stockholm Sweden Physics Division Oak Ridge National Laboratory Oak Ridge 37831 USA

We introduce a systematic and quantitative methodology for establishing the presence of neutrino oscillatory signals due to the hadron-quark phase transition (PT) in failing core-collapse supernovae from the observed neutrino event rate in water- or ice-based neutrino detectors. The methodology uses a likelihood ratio in the frequency domain as a test-statistic; it is employed for quantitative analysis of neutrino signals without assuming the frequency, amplitude, starting time, and duration of the PT-induced oscillations present in the neutrino events and thus it is suitable for analyzing neutrino signals from a wide variety of numerical simulations. We test the validity of this method by using a core-collapse simulation of a 17 solar-mass star by Zha et al. [Astrophys. J. 911, 74 (2021) ]. Based on this model, we further report the presence of a PT-induced oscillations quantitatively for a core-collapse supernovae out to a distance of ∼10 kpc, ∼5 kpc for IceCube and to a distance of ∼10 kpc, ∼5 kpc, and ∼1 kpc for a 0.4 Mt mass water Cherenkov detector. This methodology will aid the investigation of a future galactic supernova and the study of hadron-quark phase in the core of core-collapse supernovae.

关键词： Nuclear astrophysics Nuclear physics of explosive environments

The He star donor channel towards the black widow PSR J1953+1844

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arXiv 2023年

作者： Guo, Yunlang Wang, Bo Li, Xiangdong School of Astronomy and Space Science Nanjing University Nanjing210023 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education Nanjing210023 China University of Chinese Academy of Sciences Beijing100049 China Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan Observatories Chinese Academy of Sciences Kunming650216 China International Centre of Supernovae Yunnan Key Laboratory Kunming650216 China

Black widows (BWs) are a type of eclipsing millisecond pulsars (MSPs) with low companion masses ( 0.05 M☉) and tight orbits (☉ according to its mass function, indicating that the companion may be a hydrogen-deficient star. However, the origin of PSR J1953 + 1844 is highly unclear. In this paper, we explored the origin of PSR J1953 + 1844 through the neutron star+He star channel, in which the system can experience ultracompact X-ray binary phase. We found that the He star donor channel can reproduce the characteristics of PSR J1953 + 1844, indicating that this work provides an alternative formation channel for this source. Meanwhile, the minimum orbital period of BWs formed by this channel is ∼ 28 minutes, corresponding to the companion mass of 0.058 M☉. In addition, we note that even though PSR J1953 + 1844 has a short orbital period, it cannot be detected by the gravitational wave (GW) observatories like Laser Interferometer Space Antenna, TaiJi and TianQin. However, we still expect that the BWs with extremely tight orbit produced by this channel are the potential sources of future space-based GW observatories. Moreover, our simulations show that PSR J1953 + 1844 may eventually evolve into an isolated MSP. © 2023, CC0.

关键词： Pulsars

Type Ia Supernovae from First-generation Stars

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arXiv 2024年

作者： Li, Zhenwei Wang, Lifan Han, Zhanwen Chen, Xuefei Yunnan Observatories Chinese Academy of Sciences Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Science Kunming650216 China International Centre of Supernovae Yunnan Key Laboratory Kunming650216 China George P. and Cynthia Woods Mitchell Institute for Fundamental Physics & Astronomy Texas A&M University Department of Physics and Astronomy 4242 TAMU College StationTX77843 United States

Type Ia Supernovae (SNe Ia) discovered at redshift z 2.5 are presumed to be produced from Population (Pop) I/II stars. In this work, we investigate the production of SNe Ia from Pop III binaries in the cosmological framework. We derive the SN Ia rate as a function of redshift under a theoretical context for the production of first generation stars and emanate the likelihood of their detection by the James Webb Space Telescope (JWST). Assuming the initial stellar mass function (IMF) favors low-mass stars as from recent numerical simulations, we found Pop III stars may give rise to a considerable amount of SNe Ia at high redshift and Pop III stars may even be the dominant SN Ia producer at z 6. In an optimistic scenario, we expect ∼ 1(2) SNe Ia from Pop III stars at z ≈ 4(5) for a survey of area 300 arcmin2 during a 3 yr period with JWST. The same survey may record more than ∼ 400 SNe Ia at lower redshift (z 2.5) but with only about one of them from Pop III progenitors. There will be ∼ 6 Pop III SNe Ia in the same field of view at redshifts of 5 − 10. Observational constraints on SN Ia rates at the redshift range of 5 − 10 can place crucial constraints on the IMF of Pop III stars. Copyright © 2024, The Authors. All rights reserved.

关键词： Supernovae

CSS_J154915.7+375506: A low-mass-ratio marginal contact binary system with a hierarchical third body

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arXiv 2024年

作者： Wu, Jin-Feng Zhu, Li-Ying Matekov, Azizbek Li, Lin-Jia Ehgamberdiev, Shuhrat Asfandiyarov, Ildar Wang, Jiang-Jiao Zhang, Jia Meng, Fang-Bin Kunming650216 China University of Chinese Academy of Sciences No.1 Yanqihu East Rd Huairou District Beijing101408 China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650216 China Ulugh Beg Astronomical Institute of the Uzbekistan Academy of Science Astronomicheskaya 33 Tashkent100052 Uzbekistan National University of Uzbekistan 4 University str Tashkent100174 Uzbekistan

We presented the multi-filter light curves of CSS_J154915.7+375506 inaugurally, which were observed by the 1.5 m AZT-22 telescope at Maidanak Astronomical Observatory. A low-resolution spectrum obtained by LAMOST reveals it is an A-type close binary. By analyzing the BVRI total-eclipse light curves, we are able to derive a reliable photometric solution for this system, which indicates that CSS_J154915.7+375506 is an extremely low-mass-ratio (q=0.138) marginal contact binary system. The location in the HR diagram shows that its secondary component with a much smaller mass is the more evolved one, indicating the mass ratio reversal occurred. The present secondary component had transferred a significant amount of mass to the present primary one. By the combination of a total of 20 times of minimum, we investigated its O-C curve. A periodic oscillation and a possible period decrease have been detected. As the period decreases, the system will evolve towards the contact phase. This makes CSS_J154915.7+375506 a valuable case to study the formation scenario of contact binaries through mass reversal. The periodic oscillation suggested a third body with a minimal mass of 0.91 M☉, which is larger than that of the less massive component in the central binary. This implies that the secondary body was not replaced by the third body during early stellar interactions, indicating that it is a fossil system and retains its original dynamical information. © 2024, CC BY-NC-ND.

关键词： Systems (metallurgical)

Detection of 12426 SB2 candidates in the LAMOST-MRS, using a binary spectral model

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arXiv 2023年

作者： Kovalev, Mikhail Zhou, Zenghua Chen, Xuefei Han, Zhanwen Yunnan Observatories China Academy of Sciences Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650011 China Sternberg Astronomical Institute Leninskie Gory Moscow119992 Russia Center for Astronomical Mega-Science Chinese Academy of Sciences 20A Datun Road Chaoyang District Beijing100012 China

We use an updated method for the detection of double-lined spectroscopic binaries (SB2) using V sin i values from spectral fits. The method is applied to all spectra from LAMOST MRS. Using this method, we detect 12426 SB2 candidates, where 4321 are already known and 8105 are new discoveries. We check their spectra manually to minimise possible false positives. We also detect several cases of contamination of the spectra by solar light. Additionally, for candidates with multiple observations we compute mass ratios with systemic velocities and determine Keplerian orbits. We present an updated catalogue of all SB2 candidates together with additional information for some of them in separate data tables. Copyright © 2023, The Authors. All rights reserved.

关键词： Orbits

The afterglow emission from a stratified jet in GRB 170817A

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Research in Astronomy and Astrophysics 2021年第7期21卷 223-233页

作者： Kang-Fa Cheng Xiao-Hong Zhao Bin-Bin Zhang Jin-Ming Bai Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of the Chinese Academy of Sciences Beijing 100049China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210046China Department of Physics and Astronomy University of Nevada Las VegasNV 89154USA

The afterglow of GRB 170817 A has been detected for more than three years,but the origin of the multi-band afterglow light curves remains under debate.A classical top-hat jet model is faced with difficulties in producing a shallow rise of the afterglow light curves as observed(E_(v) ∝ T^(0.8)).Here we reconsider the model of stratified ejecta with an energy profile of E(> Γβ)=E_0(Γβ)^(-k) as the origin of the afterglow light curves of the burst,where Γ and β are the Lorentz factor and speed of the ejecta,respectively.k is the power-law slope of the energy *** consider that the ejecta are collimated into *** kinds of jet evolutions are investigated,including a lateral-spreading jet and a non-lateral-spreading *** fit the multi-band afterglow light curves,including the X-ray data at one thousand days post-burst,and find that both the models of the spreading and non-spreading jets can fit the light curves well,but the observed angular size of the source and the apparent velocity of the flux centroid for the spreading jet model are beyond the observation limits,while the non-spreading jet model meets the observation *** of the best-fit parameters for the non-spreading jet model,such as the number density of the circumburst medium~10^(-2) cm^(-3) and the total jet kinetic energy E ~ 4.8 × 10^(51) erg,also appear *** best-fit slope of the jet energy profile is k ~*** results suggest that the afterglow of GRB 170817 A may arise from the stratified jet and that the lateral spreading of the jet is not significant.

关键词： gamma-ray burst:general stars:jets relativistic processes

Predicting Astrometric Microlensing Events from Gaia DR3

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arXiv 2023年

作者： Su, Jie Wang, Jiancheng Zhang, Yigong Cheng, Xiangming Yang, Lei Yunnan Observatories Chinese Academy of Sciences Kunming650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing100012 China University of Chinese Academy of Sciences Beijing100049 China College of Information Engineering Kunming University Kunming650214 China

Currently astrometric microlensing is the only tool that can directly measure the mass of a single star, it can also help us to detect compact objects like isolated neutron stars and black holes. The number of microlensing events that are being predicted and reported is increasing. In the paper, the potential lens stars are selected from three types of stars, high-proper-motion stars, nearby stars and high-mass stars. For each potential lens star, we select a larger search scope to find possible matching sources to avoid missing events as much as possible. Using Gaia DR3 data, we predict 4500 astrometric microlensing events with δθ+ > 0.1mas that occur between J2010.0 and J2070.0, where 1664 events are different from those found previously. There are 293 lens stars that can cause two or more events, where 5 lens stars can cause more than 50 events. We find that 116 events have the distance of background stars from the proper motion path of lens stars more than 8′′ in the reference epoch, where the maximum distance is 16.6′′, so the cone search method of expanding the search range of sources for each potential lens star can reduce the possibility of missing events. © 2023, CC BY.

关键词： Object detection

A New Deep and Low-Mass-Ratio Contact Binary V2769 Orionis

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SSRN

SSRN 2023年

作者： Meng, Fangbin Zhu, LiYing Matekov, Azizbek Kunming650216 China University of Chinese Academy of Sciences No.1 Yanqihu East Rd Huairou District Beijing101408 China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming650216 China Ulugh Beg Astronomical Institute Uzbekistan Academy of Sciences 33 Astronomicheskaya str. Tashkent100052 Uzbekistan

We carried out the first multi-colour light curves analysis of the eclipsing binary V2769 Ori. The photometric solution was determined by applying the Wilson–Devinney method. The results show that V2769 Ori is a deep, low-mass-ratio contact binary with a mass ratio of q = 0.162(±0.003) and a contact degree of f = 55(±8)%. The total eclipse characteristics of V2769 Ori imply that the photometric solutions we obtained are reliable. With all available light minimum times, the O-C diagram was constructed and analyzed. The orbital period analysis reveals a long term period decrease at a rate of dp/dt = −1.24(±0.08) × 10−6 d yr−1 and a periodic oscillation with a period of 8.77 years. The secular period decrease can be explained by a combination of mass transfer from the more massive component to the less massive one and angular momentum loss via magnetic braking. As the orbital period decreases, the shrinking of the inner and outer critical Roche lobes causes an increase in contact degree, and the binary system will finally merge into a rapidly rotating star. Periodic oscillation may be the result of light-travel time effects due to the presence of unseen components. © 2023, The Authors. All rights reserved.

关键词： Travel time

Synchrotron Circular Polarization in Gamma-Ray Burst Prompt Optical Emission: Relativistic Thermal Electron Contribution

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arXiv 2025年

作者： Cheng, Kangfa Mao, Jirong Zhao, Xiaohong Liu, Hongbang Chen, Zhegeng Yu, Gaojin Chen, Zhifu Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and Technology Guangxi University Nanning530004 China School of Physics and Electronic Information Guangxi Minzu University Nanning530006 China Yunnan Observatories Chinese Academy of Sciences Kunming650011 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Science Kunming650011 China Center for Astronomical Mega-Science Chinese Academy of Science 20A Datun Road Chaoyang District Beijing100012 China

Synchrotron circular polarization of a non-thermal power-law electron distribution in gamma-ray bursts (GRBs) has been studied. However, some numerical simulations have shown that the resulting distribution of electrons is a combination of a thermal component and a non-thermal power-law component. In this paper, we investigate synchrotron circular polarization using such a hybrid energy distribution of relativistic thermal and nonthermal electrons within a globally toroidal magnetic field in GRB prompt optical emission. Our results show that compared to the solely nonthermal electron model, the synchrotron circular polarization degree (PD) in the hybrid electron model can vary widely in the optical band, depending on different parameters. The lower the electron temperature, the higher the circular PD. The time-averaged circular PD in the hybrid electron model can be higher than ∼ 1% when the electron temperature is as low as ∼ 1010 K, while in the solely nonthermal electron model is usually lower than ∼ 1%. We further calculate the radiative transfer of the circular and linear polarization in the optical band. Our results show that both of the circular and linear PDs decrease with the increase of optical depth, but the linear PDs decline faster than the circular PDs. To further examine the physical mechanisms of both radiation and particle acceleration, we expect that instruments will be capable of measuring the circular polarization of GRB prompt optical emission in the future. Copyright © 2025, The Authors. All rights reserved.

关键词： Circular polarization