Black Hole Formation and Black Hole Formation and KicksKicks
Vicky KalogeraPhysics & Astronomy Dept
withBart Willems
Mike HenningerTodd Levin
Natasha Ivanovaand
Chris Fryer (LANL)Frank Timmes (LANL)
Observed sample of BH X-ray binaries:
Growing in number Exciting recent measurements of proper motion
give us with radial velocity unique information on kinematic history (see F. Mirabel’s talk)
BH formation: some open questions …
What is the mass relation between progenitors and BHs ? Are asymmetric birth kicks imparted to BHs ? How do their magnitudes compare to NS kicks ?
courtesy Sky & TelescopeFeb 2003 issue
How do BHX-ray binaries form ?
primordial binary
X-ray binary at Roche-lobe overflow
Common Envelope:orbital contractionand mass loss
BH formation
Use ALL observational constraints:
Currently: donordonor position on the H-R diagramH-R diagram BH and donor massesmasses *orbital periodperiod *3-D center-of-mass velocityvelocity
Calculations: 1. Identify MT sequencesMT sequences that satisfysatisfy
H-R, masses, periodH-R, masses, period constraintsconstraints > obtain timetime of BH formationBH formation 2. Follow motion in the Galaxy > obtain post-collapse Vcmpost-collapse Vcm 3. Follow tidal evolution prior to XRB phase
> obtain post-collapse A, epost-collapse A, e4. Analyze collapse dynamics:
constrainconstrain BH XRB progenitor and kickprogenitor and kick
Example case: GRO J1655-40
Two sets of binary properties from:Beer & Podsiadlowski 2002 (BP)
Greene, Bailyn, & Orosz 2001 (GBO)
BH (Mo) Donor (Mo) SpT
BP 5.4+-0.3 1.45+-0.35 F5-G0
GBO 6.3+-0.5 2.4+-0.4 F6III
Porb = 2.62 d
GRO J1655-40 (with BP parameters)
Conservative MT:
Sequences must satisfy constraints on current H-R position of the donorand …
GRO J1655-40
Conservative MT:
Sequences must satisfy constraints on current H-R position of the donorand …
… satisfy constraintson current BH anddonor masses and most importantly orbital period
GRO J1655-40
time since BHformation: ~830Myr
chosen MT seq:4.4Mo BH2.4Mo donor1.4d period
BH
donor
GRO J1655-40 : MT seq. that satisfy all constraints
BP conservativeBP non-conservativeGBO conservativeGBO non-conservative
GRO J1655-40 : MT seq. that satisfy all constraints
BP conservativeBP non-conservativeGBO conservativeGBO non-conservative
BH
donor
GRO J1655-40: Motion in the Galaxy (for BP conservative MT seq.)
BH age ~ 830Myr ---> VPEC = 63-78 km/s
GRO J1655-40 VPEC, MBH, Mdonor, Aorb (or Porb), and e at BH formation constrain pre-collapse Apre-collapse Aorborb as well as the BH-progenitor massBH-progenitor mass and the possible BH kickpossible BH kick magnitude
(for BP conservative MT seq.)
BH kick magnitude
BH
pro
geni
tor
mas
s
GRO J1655-40 (for BP conservative MT seq.)
MBH = 4.4 Mo
from core-collapsehydro simulations:
BH formation: delayed
M0 >~ 6 Mo
GRO J1655-40
conservative MT non-conservative MT
BP
GBO
Work in progress:
Analysis for XTE J1118-480 and Cyg X-1 is underway …
Are BH kicks correlated with either BH mass or mass loss at BH formation ?
Comparison with NS systemsSco X-1, 4U1700-37, LS 5039 and more …
Conclusions on J1655-40:
BH progenitor in the range 4.5 - 14 Mo
BH kicks necessary; in the range of 30 - 200 km/s
delayed BH formation through fallback