J/ApJ/800/17 Mass-transfer sequences in 16 Galactic LMXBs (Fragos+, 2015)
The origin of black hole spin in Galactic low-mass X-ray binaries.
Fragos T., McClintock J.E.
<Astrophys. J., 800, 17 (2015)>
=2015ApJ...800...17F 2015ApJ...800...17F
ADC_Keywords: Binaries, X-ray ; Spectral types ; Stars, masses
Keywords: binaries: close; black hole physics; Galaxy: stellar content;
stars: black holes; stars: evolution; X-rays: binaries
Abstract:
Galactic field black hole (BH) low-mass X-ray binaries (LMXBs) are
believed to form in situ via the evolution of isolated binaries. In
the standard formation channel, these systems survived a common
envelope phase, after which the remaining helium core of the primary
star and the subsequently formed BH are not expected to be highly
spinning. However, the measured spins of BHs in LMXBs cover the whole
range of spin parameters. We propose here that the BH spin in LMXBs is
acquired through accretion onto the BH after its formation. In order
to test this hypothesis, we calculated extensive grids of detailed
binary mass-transfer sequences. For each sequence, we examined
whether, at any point in time, the calculated binary properties are in
agreement with their observationally inferred counterparts of 16
Galactic LMXBs. The "successful" sequences give estimates of the mass
that the BH has accreted since the onset of Roche-Lobe overflow. We
find that in all Galactic LMXBs with measured BH spin, the origin of
the spin can be accounted for by the accreted matter, and we make
predictions about the maximum BH spin in LMXBs where no measurement is
yet available. Furthermore, we derive limits on the maximum spin that
any BH can have depending on current properties of the binary it
resides in. Finally we discuss the implication that our findings have
on the BH birth-mass distribution, which is shifted by ∼1.5M☉
toward lower masses, compared to the currently observed one.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 114 17 Currently observed properties of 16 Galactic
LMXBs with a dynamically confirmed BH and at
least an orbital period measurement
table5.dat 98 4258 Selected properties of all individual mass-transfer
(MT) sequences calculated to satisfy simultaneously
all the observational constraints, for each of the
BH LMXBs in Table 2
refs.dat 63 47 References
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See also:
J/MNRAS/426/1701 : High-frequency QPO in black hole binaries (Belloni+, 2012)
J/ApJ/719/L79 : BH spin-orbit misalignment in Galactic XRBs (Fragos+, 2010)
J/ApJ/699/453 : Determination of black hole masses (Shaposhnikov+, 2009)
J/A+A/469/807 : Catalogue of Galactic low-mass X-ray binaries (Liu+, 2007)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Symbol Symbol used in figures (1)
9- 21 A13 --- ID LMXB identifier
23- 25 A3 --- n_ID Note on GRO J1655-40 (G1)
27- 31 F5.2 Msun MBH [5.4/12.4] Black Hole mass
33- 36 F4.2 Msun e_MBH [0.2/2] MBH uncertainty
38 A1 --- f_MBH [g] Unreliable MBH (2)
40- 43 F4.2 Msun M2 [0.1/2.9]? Donor star mass
45- 48 F4.2 Msun e_M2 [0.05/1]? M2 uncertainty
50- 55 F6.3 d Per [0.1/34]? Orbital period
57- 67 A11 --- SpT MK spectral type of the donor star
69- 73 I5 [K] Teff [2905/10500]? Temperature or lower range if
Tup is filled
75- 78 I4 [K] Tup [4378/6466]? Upper range of temperature
80- 82 I3 [K] e_Teff [200/500]? Teff uncertainty
84 A1 --- f_Teff [s] Teff inferred from spectral type (3)
86- 89 F4.2 --- a* [0.05/1]? Black Hole spin parameter a* (5)
91- 94 F4.2 --- e_a* ? a* uncertainty
95 A1 --- f_a* [d] Flag on a* (4)
97-114 A18 --- Ref Reference(s) (see refs.dat file)
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Note (1): Filled symbols (first 6 rows: square, triangle-down, triangle-up,
triangle-right, losange, circle) correspond to systems for which the
BH spin has been measured using the continuum-fitting method, and open
symbols systems (the following 4 lines) for which the BH spin has
been estimated via the jet power-BH spin correlation. Each symbol
corresponds to the same system in all figures for the rest of the paper.
Note (2): No reliable or accurate dynamical BH mass measurement is available
for this system. Instead, the BH mass reported in this table is a
fiducial value based on the derived BH mass distribution by Ozel et al.
(2010ApJ...725.1918O 2010ApJ...725.1918O).
For GX 339-4 this value is also consistent with a BH mass of
7.5±0.8M☉ reported by Chen T. (2011, Jets at all Scales (IAU
Symp. 275), ed. G. Romero, R. Sunyaev, & T. Bellon (Cambridge: Cambridge
Univ. Press), 327) based on X-ray timing data.
Note (3): Donor star's effective temperature. When the value is denoted
with a "s", Teff is not directly measured, but is instead inferred by
the reported spectral type. All transformations of spectral types to
effective temperatures were done based on the tables provided in Gray
(2008oasp.book.....G 2008oasp.book.....G) and Cox A. (2000, Allen's Astrophysical
Quantities, 4th ed. (New York: AIP)), assuming typical one-standard
deviation uncertainties of: ±1000K for O9V-B2V stars, ±250K for
B3V-B9V, ±100K for A0V-M6V, ±100K for F0III-F9III, ±50K for
G0III-M5III, and ±70K for M0III-M6III. When there is a discrepancy
between the values reported in Gray and Cox, the combined effective
temperature range from the two tables is taken into account.
Note (4): When the value is denoted with a "d", a* is not directly measured
but estimated from the maximum jet power of the system
(Steiner et al. 2013ApJ...762..104S 2013ApJ...762..104S).
Note (5): the spin parameter is a dimensionless parameter defined as
a* = cJ/(GM2), where M is the mass and J the angular momentum of
the black hole.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- ID LMXB identifier
14- 16 A3 --- n_ID Note on GRO J1655-40 (G1)
18 A1 --- f_ID [d] No "succesful" Mass Transfer sequence (1)
20- 23 I4 --- Seq [1/2184] Mass Transfer (MT) Sequence number
25 A1 --- n_Seq [b] Good MT sequence (2)
27- 30 F4.1 Msun MBHon [3/10] Blackhole mass at onset of Roche-lobe
overflow (RLO)
32- 35 F4.1 Msun M2on [0.6/10] Donor mass at onset of RLO
37- 41 F5.2 d Pon [0.2/30] Orbital period at onset of RLO
43- 46 F4.2 --- X2on [0/0.7] Central H fraction of donor at onset
of Roche-lobe overflow (RLO)
48- 52 F5.2 Gyr tau2on [0/12.4] Donor age at onset of RLO
54- 57 F4.1 Msun MBH [4.8/15.4] Current blackhole mass
59- 62 F4.2 Msun M2 [0/3] Current donor mass
64- 67 F4.2 [K] logT [2.5/4.1] Log of donor current effective
temperature
69- 72 F4.2 --- X2 [0/0.7] Current donor star H fraction
74- 78 F5.2 Gyr tau2 [0.04/14] Current donor age
80- 83 F4.2 Msun B_Macc [0.02/9] Maximum mass amount blackhole can
accrete (3)
85- 88 F4.2 Msun Macc [0/5.5] Accreted mass (4)
90- 93 F4.2 --- B_a* [0.01/1] Maximum spin parameter blackhole can
acquire (3)
95- 98 F4.2 --- a* [0/1] Spin parameter (4)
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Note (1): No "succesful" MT sequences were found for V4641 Sgr assuming fully
conservative MT. The values reported for this system are assuming an
accretion efficiency of 50%. See text for details.
Note (2): A MT sequence that satisfy simultaneously all the observational
constraints including the measured or estimated black hole spin.
Note (3): Assuming fully conservative MT.
Note (4): Assuming that the accretion rate could not exceed the Eddington limit.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference code
4- 22 A19 --- BibCode ADS bibcode if any
24- 48 A25 --- Aut Author's name(s)
50- 63 A14 --- Comm Comment
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Global notes:
Note (G1): GBO, BP: two analyses for the determination of the BH and
companion mass are available in the literature for GRO J1655-40, the
one by Greene et al. (2001ApJ...554.1290G 2001ApJ...554.1290G) denoted in the table by the
superscript "GBO," and the one by Beer & Podsiadlowski
(2002MNRAS.331..351B 2002MNRAS.331..351B) denoted by the superscript "BP." At present it
is unclear which of the two analyses (GBO or BP) yields the most
reliable estimates of MBH and M2. We therefore consider both sets of
constraints and study them as two separate cases.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 25-Jun-2015