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Limits from the Hubble Space Telescope on a Point Source in SN 1987A
Limits from the Hubble Space Telescope on a Point Source in SN 1987A The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Graves, Genevieve J. M., Peter M. Challis, Roger A. Chevalier, Arlin Crotts, Alexei V. Filippenko, Claes Fransson, Peter Garnavich, et al. 2005. “Limits from the Hubble Space Telescopeon a Point Source in SN 1987A.” The Astrophysical Journal 629 (2): 944–59. https:// doi.org/10.1086/431422. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:41399924 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA The Astrophysical Journal, 629:944–959, 2005 August 20 # 2005. The American Astronomical Society. All rights reserved. Printed in U.S.A. LIMITS FROM THE HUBBLE SPACE TELESCOPE ON A POINT SOURCE IN SN 1987A Genevieve J. M. Graves,1, 2 Peter M. Challis,2 Roger A. Chevalier,3 Arlin Crotts,4 Alexei V. Filippenko,5 Claes Fransson,6 Peter Garnavich,7 Robert P. Kirshner,2 Weidong Li,5 Peter Lundqvist,6 Richard McCray,8 Nino Panagia,9 Mark M. Phillips,10 Chun J. S. Pun,11,12 Brian P. Schmidt,13 George Sonneborn,11 Nicholas B. Suntzeff,14 Lifan Wang,15 and J. Craig Wheeler16 Received 2005 January 27; accepted 2005 April 26 ABSTRACT We observed supernova 1987A (SN 1987A) with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST ) in 1999 September and again with the Advanced Camera for Surveys (ACS) on the HST in 2003 November. -
1 NASA Goddard Space Flight Center
Source of Acquisition 1 NASA Goddard Space Flight Center \> SN 1987A AFTER 18 YEARS: MID-INFRARED GEMINI and SPITZER OBSERVATIONS OF THE REMNANT Patrice Bouchet1,2, Eli Dwek3, John Danziger4, Richard G. Arendt 5, I. James M. De Buizer', Sangwook Park7, Nicholas B. SuntzefF2, Robert P. Kirshners, and Peter Challis ABSTRACT We present high resolution 11.7 and 18.3 pm mid-IR images of SN 1987A obtained on day 6526 since the explosion with the Thermal-Region Camera and Spectrograph (T-ReCS) attached to the Gemini South 8m telescope. The 11.7 pm flux has increased significantly since our last observations on day 6067. The images clearly show that all the emission arises from the equatorial ring (ER). Nearly contemporaneous spectra obtained on day 6184 with the MIPS at 24 pm, on day 6130 with the IRAC in 3.6- 8 pm region, and on day 6190 with the IRS in the 12-37 ,urn instruments on board the Spitzer Space Telescope's show that the emission consists of thermal emission from silicate dust that condensed out in the red giant wind of the progenitor star. The dust temperature is 1662:; K, and the emitting dust mass is (2.6:;;:) x MB.Lines of [Ne 111 12.82 pm and [Ne 1111 15.56 pm are clearly present in the Spitzer spectrum, as well as a weak [Si 113 34.8 pm line. We also detect two lines near 26 pm which we tentatively ascribe to [Fe 117 25.99 pm and [0 IV] 25.91 pm. Comparison of the mid-IR Gemini 11.7 pm image with X-ray images obtained by Chandra, UV- optical images obtained by HST, and radio synchrotron images obtained by the ATCA show generally good correlation of the images across all wavelengths. -
Supernova Neutrinos in the Proto-Neutron Star Cooling Phase and Nuclear Matter
TAUP 2019 IOP Publishing Journal of Physics: Conference Series 1468 (2020) 012089 doi:10.1088/1742-6596/1468/1/012089 Supernova neutrinos in the proto-neutron star cooling phase and nuclear matter Ken’ichiro Nakazato1 and Hideyuki Suzuki2 1 Faculty of Arts and Science, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan 2 Faculty of Science & Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan E-mail: [email protected] Abstract. A proto-neutron star (PNS) is a newly formed compact object in a core collapse supernova. Using a series of phenomenological equations of state (EOS), we have systematically investigated the neutrino emission from the cooling phase of a PNS. The numerical code utilized in this study follows a quasi-static evolution of a PNS solving the general-relativistic stellar structure with neutrino diffusion. As a result, the cooling timescale evaluated from the neutrino light curve is found to be long for the EOS models with small neutron star radius and large effective mass of nucleons. It implies that extracting properties of a PNS (such as mass and radius) and the nuclear EOS is possible by a future supernova neutrino observation. 1. Introduction Core collapse supernovae, which are the spectacular death of massive stars, emit an enormous amount of neutrinos. In the case of SN1987A, a few tens of events were actually detected [1, 2, 3] and contributed to confirm the standard scenario for supernova neutrino emission. Although the neutron star formed in SN1987A has not yet been observed, its mass estimations had been attempted by using the neutrino event number [4, 5]. -
The Distance to the Large Magellanic Cloud
Proceedings Astronomy from 4 perspectives 1. Cosmology The distance to the large magellanic cloud Stefan V¨olker (Jena) In the era of modern cosmology it is necessary to determine the Hubble constant as precise as possible. Therefore it is important to know the distance to the Large Mag- ellanic Cloud (LMC), because this distance forms the fundament of the cosmological distance ladder. The determination of the LMC's distance is an suitable project for highschool students and will be presented in what follows. Calculating the distance to the LMC using the supernova SN 1987 A [1, 2] By combining the angular size α of an object with its absolute size R, one can calculate the distance d (at least for our cosmological neighborhood) using the equation R R d = ≈ (1) tan α α and the approximation d R. In the case of the SN 1987 A students can measure the angular size of the circumstellar ring on the Hubble Space Telescope (HST) image (Figure 1). The absolute size of the ring can be derived from the delay time due to light-travel effects seen in the emission light curve (also Figure 1). Once the supernova exploded, the UV-flash started 1,00 0,75 0,50 intensity (normalized) 0,25 0 0 500 1000 time t/d ESA/Hubble tP1' tP2' Figure 1: left: HST picture of the SN 1987 A; right: emission light curve of the circumstellar [2, 3] propagating and reached the whole ring at the same time, which started emitting immediately. The additional distance x is linked to the delay time by the equation x = c · ∆t = c · (t 0 − t 0 ). -
Neutrinos from Core-Collapse Supernovae and Binary Neutron Star Mergers
Neutrinos from core-collapse supernovae and binary neutron star mergers Maria Cristina Volpe Astroparticules et Cosmologie (APC), Paris, France Sun core-collapse Supernovae McLaughlin Perego et al, 2014 accretion disks around black holes or neutron star mergers remnants Solar neutrino observations Vacuum averaged oscillations pep MSW solution 7Be 8B ν Survival Probability e Borexino, Nature 512 (2014) ν Neutrino Energy (MeV) Vacuum-averaged oscillations versus MSW suppression of high energy 8B neutrinos. Energy production of low mass main sequence stars confirmed — pp reaction chain. Future measurement of CNO neutrinos - main energy production in massive main sequence stars. The Mikheev-Smirnov-Wolfenstein effect Neutrinos interact with matter and undergo resonant adiabatic flavor conversion. Wolfenstein PRD (1978) Mikheev, Smirnov(1985) hmat = p2GF ⇢e mean-field approximation matter basis flavour basis ~ ν2 =νe ν , ν ν ν ~ ν2 µ τ e 2 ~ ν 1 =νµ ν~ 1 Effective mass Effective vacuum ν1 MSW resonance DENSITY 2 ∆m˜ /4E i✓˙M h⌫ = − − neutrino hamiltonian in the matter basis i✓˙ ∆m˜ 2/4E ✓ M ◆ ✓˙M Resonance condition : Adiabaticity : γ = | 2 | << 1 h h 0 ∆m˜ /4E ⌫,11 − ⌫,22 ⇡ Also in supernovae, in accretion disks around compact objects, in the Earth and in the Early Universe (BBN epoch) Heavy elements nucleosynthesis Two main mechanisms at the origin of elements heavier than iron : s-process (s-slow) and r-process (r-rapid). Double peak structures at the first A=90, the second A=130 and third A=190 peaks due to both the s-process and the r-process. The r-process sites : a longstanding question The r-process : neutron-capture is fast compared to half-lives of neutron-rich unstable nuclei. -
Gas and Dust in the Magellanic Clouds
Gas and dust in the Magellanic clouds A Thesis Submitted for the Award of the Degree of Doctor of Philosophy in Physics To Mangalore University by Ananta Charan Pradhan Under the Supervision of Prof. Jayant Murthy Indian Institute of Astrophysics Bangalore - 560 034 India April 2011 Declaration of Authorship I hereby declare that the matter contained in this thesis is the result of the inves- tigations carried out by me at Indian Institute of Astrophysics, Bangalore, under the supervision of Professor Jayant Murthy. This work has not been submitted for the award of any degree, diploma, associateship, fellowship, etc. of any university or institute. Signed: Date: ii Certificate This is to certify that the thesis entitled ‘Gas and Dust in the Magellanic clouds’ submitted to the Mangalore University by Mr. Ananta Charan Pradhan for the award of the degree of Doctor of Philosophy in the faculty of Science, is based on the results of the investigations carried out by him under my supervi- sion and guidance, at Indian Institute of Astrophysics. This thesis has not been submitted for the award of any degree, diploma, associateship, fellowship, etc. of any university or institute. Signed: Date: iii Dedicated to my parents ========================================= Sri. Pandab Pradhan and Smt. Kanak Pradhan ========================================= Acknowledgements It has been a pleasure to work under Prof. Jayant Murthy. I am grateful to him for giving me full freedom in research and for his guidance and attention throughout my doctoral work inspite of his hectic schedules. I am indebted to him for his patience in countless reviews and for his contribution of time and energy as my guide in this project. -