An ultra-massive, fast-spinning white dwarf in a peculiar binary system S. Mereghetti (1), A.Tiengo (1), P. Esposito (1), N. La Palombara (1), G.L.Israel.

Slides:

Advertisements

Similar presentations

Proton Cyclotron Lines in Thermal Magnetar Spectra S. Zane, R. Turolla, L. Stella and A. Treves Mullard Space Science Laboratory UCL, University of Padova,

Advertisements

X-ray pulsars in wind-fed accretion systems 王伟 (NAOC) July 2009, Pulsar Summer School Beijing.

Low Mass X-Ray Binaries and X-Ray Bursters NTHU Yi-Kuan Chiang 2007/12/13.

ASTR Fall Semester Joel E. Tohline, Alumni Professor Office: 247 Nicholson Hall [Slides from Lecture17]

Weighing in on Neutron Stars Varun Bhalerao California Institute of Technology Collaborators: F. Harrison, S. Kulkarni, Marten van Kerkwijk, and others.

Lecture I: Introduction to White Dwarfs S. R. Kulkarni, E. Ofek

Lecture 26: The Bizarre Stellar Graveyard: White Dwarfs and Neutron Stars.

Small is Beautiful: Cataclysmic Variables from the SDSS John Southworth Boris Gänsicke Tom Marsh + many others.

End States Read Your Textbook: Foundations of Astronomy

RXTE Observations of Cataclysmic Variables and Symbiotic Stars Koji Mukai NASA/GSFC/CRESST and UMBC.

Neutron Stars and Black Holes Please press “1” to test your transmitter.

2009 July 8 Supernova Remants and Pulsar Wind Nebulae in the Chandra Era 1 Modeling the Dynamical and Radiative Evolution of a Pulsar Wind Nebula inside.

Accretion in Binaries Two paths for accretion –Roche-lobe overflow –Wind-fed accretion Classes of X-ray binaries –Low-mass (BH and NS) –High-mass (BH and.

Mass transfer in a binary system

AS 3004 Stellar Dynamics Mass transfer in binary systems Mass transfer occurs when –star expands to fill Roche-lobe –due to stellar evolution –orbit, and.

Neutron Stars and Black Holes

Neutron Stars Chandrasekhar limit on white dwarf mass Supernova explosions –Formation of elements (R, S process) –Neutron stars –Pulsars Formation of X-Ray.

Supernova. Explosions Stars may explode cataclysmically. –Large energy release (10 3 – 10 6 L  ) –Short time period (few days) These explosions used.

ASTR 113 – 003 Spring 2006 Lecture 07 March 8, 2006 Review (Ch4-5): the Foundation Galaxy (Ch 25-27) Cosmology (Ch28-39) Introduction To Modern Astronomy.

Neutron Stars and Black Holes Chapter 14. The preceding chapters have traced the story of stars from their birth as clouds of gas in the interstellar.

HOW MANY NEUTRON STARS ARE BORN RAPIDLY ROTATING? HOW MANY NEUTRON STARS ARE BORN RAPIDLY ROTATING? NIKOLAOS STERGIOULAS DEPARTMENT OF PHYSICS ARISTOTLE.

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display 1 Announcements Homework #10: Chp.14: Prob 1, 3 Chp. 15: Thought.

Neutron Stars Chapter Twenty-Three.

White Dwarfs and Neutron Stars White dwarfs –Degenerate gases –Mass versus radius relation Neutron stars –Mass versus radius relation –Pulsars, magnetars,

Radio-quiet Isolated Neutron Stars (RQINs) Jeng-Lwen, Chiu Institute of Astronomy, NTHU 2004/09/30.

Neutron stars - Chapter Neutron stars The remains of cores of some massive stars that have become supernovae. Cores are a degenerate gas of mostly.

1. White Dwarf If initial star mass < 8 M Sun or so. (and remember: Maximum WD mass is 1.4 M Sun, radius is about that of the Earth) 2. Neutron Star If.

Two stories from the life of binaries: getting bigger and making magnetars Sergei Popov, Mikhail Prokhorov (SAI MSU) This week SAI celebrates its 175 anniversary.

White Dwarfs. References D. Koester, A&A Review (2002) “White Dwarfs: Recent Developments” Hansen & Liebert, Ann Rev A&A (2003) “Cool White Dwarfs” Wesemael.

Faint X-ray sources in globular clusters – an XMM-Newton view Natalie Webb Toulouse, France & Didier Barret.

Compact Objects Astronomy 315 Professor Lee Carkner Lecture 15.

ASTR377: A six week marathon through the firmament by Orsola De Marco Office: E7A 316 Phone: Week 6, May 24-27, 2009.

Constraining Neutron Star Radii and Equations of State Josh Grindlay Harvard (collaboration with Slavko Bogdanov McGill Univ.)

Black holes: do they exist?

He star evolutionary channel to intermediate-mass binary pulsars with a short-orbital-period Chen Wen-Cong School of Physics, Peking University Department.

RXJ a soft X-ray excess in a low luminosity accreting pulsar La Palombara & Mereghetti astro-ph/

SSS in young stellar populations: progenitors of the “prompt” Sne Ia? Thomas Nelson NASA Goddard Space Flight Center University of Maryland – Baltimore.

Lars Bildsten Kavli Institute for Theoretical Physics University of California Santa Barbara Unusual Binaries made via Interactions.

The Brightest point X-ray sources in elliptical galaxies and the mass spectrum of accreting black holes N. Ivanova, V. Kalogera astro-ph/

Is Radio−Ejection ubiquitous among Accreting Millisecond Pulsar? Luciano Burderi, University of Cagliari Collaborators: Tiziana di Salvo, Rosario Iaria,

Dec. 6, Review: >8Msun stars become Type II SNe As nuclear burning proceeds to, finally, burning Silicon (Si) into iron (Fe), catastrophe looms.

Outburst of LS V detected by MAXI, RXTE, Swift Be X-ray Binary LS V INTRODUCTION - Be X-ray Binary consists of a neutron star and Be star.

Current Status of Neutron Stars: Astrophysical Point of View Chang-Hwan 1.

THE PECULIAR EVOLUTIONARY HISTORY OF IGR J IN TERZAN 5 A. Patruno Reporter: Long Jiang ( 姜龙 )

The Radio Millisecond Pulsar PSR J : A Link to Low-Mass X-Ray Binaries Slavko Bogdanov.

Observations of AXPs and SGRs: 1E and SGR Andrea Tiengo (IASF-MI, Univ. Milano) S. Mereghetti, G. L. Israel, L. Stella, S. Zane, A.

Dec. 11, Review Neutron Stars(NSs) and SNR (Crab Nebula…) and then on to BHs… SN-II produce a NS for massive stars in approx. range 8-15Msun; and.

Black holes and accretion flows Chris Done University of Durham.

Black Holes Accretion Disks X-Ray/Gamma-Ray Binaries.

Death of Stars II Physics 113 Goderya Chapter(s): 14

Supercritical Accretion in the Evolution of Neutron Star Binaries and Its Implications Chang-Hwan 1 Nuclear Physics A 928 (2014)

Goal: To understand special stars. Objectives: 1)To learn about Neutron Stars 2)To learn about Pulsars 3)To understand Stars that erupt.

1 Chang-Hwan Spin of Stellar Mass Black Holes: Hypernova and BH Spin Correlation in Soft X-ray BH Binaries.

Binary Orbits. Orbits Binary Stellar Systems 1/3 to 2/3 of stars in binary systems Rotate around center of mass (barycenter) Period - days to years for.

Evolutionary Sequences For Low- And-Intermediate-Mass X-Ray Binaries Ph. Podsiadlowski S. Rappaport E. D. Pfahl.

Progenitor stars of supernovae Poonam Chandra Royal Military College of Canada.

Observational Evidence for Quasi-soft X-Ray Sources in Nearby Galaxies and the link to Intermediate-mass Black Holes Albert Kong and Rosanne Di Stefano.

High Energy Astrophysics

References: 1. Bhattacharya & van den Heuvel, Phys Reports, vol 203, 1, X-ray Binaries, edited by Lewin, van Paradijs, and van den Heuvel, 1995,

SS433 / W50 – still an enigma ! History SS433 main properties Modeling the jets Physical parameters and problems ! Interaction of a jet with its surrounding.

Accretion High Energy Astrophysics

The Magnetic Field of an Isolated Neutron Star from X-ray Cyclotron Absorption Lines G.F.Bignami (1,2) P.A.Caraveo (3) A.De Luca (3,4) S.Mereghetti (3)

Formation of Redback and Black Widow Binary Millisecond Pulsars

Accretion High Energy Astrophysics

Ch 12--Life Death of Stars

Mariko KATO (Keio Univ., Japan) collaboration with

Evolution of the Solar System

Final states of a star: 1. White Dwarf

Evolutionary Link between X-ray Pulsars and Millisecond Radio Pulsars

Presentation transcript:

An ultra-massive, fast-spinning white dwarf in a peculiar binary system S. Mereghetti (1), A.Tiengo (1), P. Esposito (1), N. La Palombara (1), G.L.Israel (2), L.Stella (2) 1) INAF – IASF MILANO 2) INAF Oss. Astron. ROMA

HD : a single-lined spectroscopic binary Hot subdwarf (sdO type ) B = 8 mag HD S. MEREGHETTI - Tuebingen - Aug 18, ? Companion invisible in optical / UV data

The brightest sdO Heber 2009, ARAA HD T = 47,500 K L ~ 10 4 L sun Log g = 4.25 S. MEREGHETTI - Tuebingen - Aug 18, 2010

HD the brightest sdO  well studied single-lined spectroscopic binary Hydrogen poor, Helium rich P orb = (32) days circular orbit Optical mass function / Msun Thackeray 1970Kudritzky et al Hamann et al. 1981Bruhweiler et al Stickland & Lloyd 1984Bisscheroux et al Hamann 2010Przybilla et al 2010 S. MEREGHETTI - Tuebingen - Aug 18, 2010

Optical mass function Invisible companion’s mass HD mass S. MEREGHETTI - Tuebingen - Aug 18, 2010

Discovery of X-ray periodicity ROSAT  Soft X-ray source P = 13.2 s (Israel et al. 1997, ApJ) The companion is either a Neutron Star or a White Dwarf

XMM-Newton observation 44 ks observation on May 10, 2008 Soft BB + hard component spectrum L x = pc ( keV) kT=39 eV  ~ 2 N H = cm -2 S. MEREGHETTI - Tuebingen - Aug 18, 2010 The companion is a White Dwarf

JD Period (s) XMM-Newton results: timing S. MEREGHETTI - Tuebingen - Aug 18, 2010 dP/dt < s/s P = (4) s keV keV Pulsed fraction 62%

Time delays in X-ray pulses X-ray projected semi major-axis : Ax sini = / light-sec + opt. mass funct.  q = M HD /Mx = / S. MEREGHETTI - Tuebingen - Aug 18, 2010

Optical + X-ray mass functions M HD /Mx = 1.17 Mx M HD S. MEREGHETTI - Tuebingen - Aug 18, 2010

Discovery of X-ray eclipse Eclipse duration = 1.3 hours Radius of HD = 1.45+/-0.25 Rsun  inclination 79—84 degrees S. MEREGHETTI - Tuebingen - Aug 18, 2010

Opt. and X-ray m.f. + inclination Mx = 1.28 Msun M HD = 1.5 Msun S. MEREGHETTI - Tuebingen - Aug 18, 2010

M HD = / M sun M wd = / M sun The companion of HD49798 is a very massive white dwarf S. MEREGHETTI - Tuebingen - Aug 18, 2010

Dynamical measurement  Robust, ‘’assumptions-free” result  not dependent on Mass-Radius relation Most WD masses are derived indirectly: spectroscopic and photometric methods  L, T, log g  M/R 2 gravitational redshift  M/R and rely on M-R relation to finally get M S. MEREGHETTI - Tuebingen - Aug 18, 2010 The companion of HD49798 is a very massive white dwarf M wd = / M sun

Past evolution S. MEREGHETTI - Tuebingen - Aug 18, 2010

Future evolution S. MEREGHETTI - Tuebingen - Aug 18, 2010 The WD is currently accreting in the wind of HD49798 When HD49798 evolves it will fill its Roche-lobe again Stable mass transfer of a few tenths of Msun onto the WD The WD will reach the Chandra limit

The fastest spinning white dwarf P=13.2 s (only ~5 times slower than break-up) Fast spin gives a limit on R WD < 7000 km Accretion implies low magnetic field (to avoid the propeller effect)  B < few kG Origin of fast rotation: spun-up by accretion ?? when ? why not to an even shorter P ? rapidly rotating at birth ? S. MEREGHETTI - Tuebingen - Aug 18, 2010

Conclusions Robust, dynamical determination of M > 1.2 Msun for a white dwarf Post Common Envelope binary with well determined masses  optimal test-bench for evolutionary models The fastest spinning WD (P=13.2 s)  low B to avoid propeller ( < few kG) Possible future evolution: - SN Ia with short delay time or - non-recycled millisecond pulsar S. MEREGHETTI - Tuebingen - Aug 18, 2010