J/ApJ/914/121 Limits on SMBH binaries from NANOGrav (Arzoumanian+, 2021)
The NANOGrav 11yr data set: limits on supermassive black hole binaries in
galaxies within 500Mpc.
Arzoumanian Z., Baker P.T., Brazier A., Brook P.R., Burke-Spolaor S.,
Becsy B., Charisi M., Chatterjee S., Cordes J.M., Cornish N.J., Crawford F.,
Cromartie H.T., DeCesar M.E., Demorest P.B., Dolch T., Elliott R.D.,
Ellis J.A., Ferrara E.C., Fonseca E., Garver-Daniels N., Gentile P.A.,
Good D.C., Hazboun J.S., Islo K., Jennings R.J., Jones M.L., Kaiser A.R.,
Kaplan D.L., Kelley L.Z., Key J.S., Lam M.T., Lazio T.J.W., Luo J.,
Lynch R.S., Ma C.-P., Madison D.R., McLaughlin M.A., Mingarelli C.M.F.,
Ng C., Nice D.J., Pennucci T.T., Pol N.S., Ransom S.M., Ray P.S.,
Shapiro-Albert B.J., Siemens X., Simon J., Spiewak R., Stairs I.H.,
Stinebring D.R., Stovall K., Swiggum J.K., Taylor S.R., Vallisneri M.,
Vigeland S.J., Witt C.A., The NANOGrav Collaboration.
<Astrophys. J., 914, 121 (2021)>
=2021ApJ...914..121A 2021ApJ...914..121A
ADC_Keywords: Black holes; Gravitational wave; Galaxies, nearby; Galaxies, IR
Keywords: Galaxies ; Supermassive black holes ; Gravitational waves
Abstract:
Supermassive black hole binaries (SMBHBs) should form frequently in
galactic nuclei as a result of galaxy mergers. At subparsec
separations, binaries become strong sources of low-frequency
gravitational waves (GWs), targeted by Pulsar Timing Arrays. We used
recent upper limits on continuous GWs from the North American
Nanohertz Observatory for Gravitational Waves (NANOGrav) 11yr data set
to place constraints on putative SMBHBs in nearby massive galaxies. We
compiled a comprehensive catalog of ∼44000 galaxies in the local
universe (up to redshift ∼0.05) and populated them with hypothetical
binaries, assuming that the total mass of the binary is equal to the
SMBH mass derived from global scaling relations. Assuming circular
equal-mass binaries emitting at NANOGrav's most sensitive frequency of
8nHz, we found that 216 galaxies are within NANOGrav's sensitivity
volume. We ranked the potential SMBHBs based on GW detectability by
calculating the total signal-to-noise ratio such binaries would induce
within the NANOGrav array. We placed constraints on the chirp mass and
mass ratio of the 216 hypothetical binaries. For 19 galaxies, only
very unequal-mass binaries are allowed, with the mass of the secondary
less than 10% that of the primary, roughly comparable to constraints
on an SMBHB in the Milky Way. However, we demonstrated that the
(typically large) uncertainties in the mass measurements can weaken
the upper limits on the chirp mass. Additionally, we were able to
exclude binaries delivered by major mergers (mass ratio of at least
1/4) for several of these galaxies. We also derived the first limit on
the density of binaries delivered by major mergers purely based on GW
data.
Description:
In this paper, we expand on the work of Schutz & Ma (2016MNRAS.459.1737S 2016MNRAS.459.1737S)
considering the most recent (and most sensitive) continuous wave (CW)
upper limits from the North American Nanohertz Observatory for
Gravitational waves (NANOGrav), derived from the 11yr data set
(Arzoumanian+ 2018ApJS..235...37A 2018ApJS..235...37A & Aggarwal+ 2019ApJ...880..116A 2019ApJ...880..116A).
This data set spans from 2004 to 2015 and contains times of arrival
(TOAs) of 45 pulsars.
We construct a comprehensive galaxy catalog, which contains all the
massive nearby galaxies, using the Two Micron All-Sky Survey (2MASS).
Our starting point was the 2MASS Redshift Survey (2MRS;
Huchra+ 2012, J/ApJS/199/26), which consists of 43533 galaxies, the
redshifts of which have been measured spectroscopically. We carefully
determine the galaxy distances and the masses of their supermassive
black hole binaries (SMBHBs). We select a subset of 216 galaxies that
are in the sensitivity volume of NANOGrav, i.e., they would emit
detectable gravitational waves (GWs) if they hosted equal-mass
circular binaries at 8nHz.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 54 43533 2MRS galaxy catalog with estimates of the supermassive
black hole (SMBH) mass and distance, along with the
GW strain upper limit towards the direction of
each galaxy
table3.dat 91 216 The 95% mass ratio upper limits as a function of
frequency for the galaxies in the NANOGrav volume
ranked by the mean S/N of putative equal-mass
circular binaries at 8nHz
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/ApJ/655/790 : Groups of galaxies in 2MASS survey (Crook+, 2007)
J/ApJS/199/26 : The 2MASS Redshift Survey (2MRS) (Huchra+, 2012)
J/ApJ/795/158 : The MASSIVE survey : 116 candidate galaxies (Ma+, 2014)
J/MNRAS/453/1562 : CRTS close supermassive black hole binaries (Graham+, 2015)
J/ApJ/808/183 : NGC1271 stellar kinematics (Walsh+, 2015)
J/MNRAS/458/3341 : 42ms pulsars high-precision timing (Desvignes+, 2016)
J/AJ/152/50 : Cosmicflows-3 catalog (CF3) (Tully+, 2016)
J/ApJ/817/2 : High angular res. spectroscopy of NGC 1277 (Walsh+, 2016)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- 2MASX Source Name (JHHMMSSss+DDMMSSs)
18- 23 F6.2 Mpc Dist [-0.91/736.91] Galaxy Distance in Mpc
25- 29 F5.2 [Msun] BHMblg1 [1.8/10.32]?=-9 SMBH mass assuming fbulge=1
31- 35 F5.2 [Msun] BHMblg0.31 [1.28/10.32]?=-9 SMBH mass assuming
fbulge=0.31
37- 41 F5.2 [Msun] e_BHMblg1 [0/0.5]?=-9 SMBH mass uncertainty
43- 50 A8 --- GWstrain GW strain upper limit at the pixel
of the galaxy
52- 52 I1 --- f_Dist [1/3] Flag for distance estimate (1)
54- 54 I1 --- f_BHMblg1 [1/6] Flag for mass estimate (2)
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Note (1): Flag for distance estimate (see Section 2.1) as follows:
1 = Cosmicflows-3 (Tully+ 2016, J/AJ/152/50)
2 = Groups Catalog (Crook+ 2007, J/ApJ/655/790)
3 = flow field model.
Note (2): Flag for mass estimate (see Section 2.2) as follows:
1 = dynamical measurement (77 occurrences);
2 = reverberation mapping for AGN (29 occurrences);
3 = M-sigma (2206 occurrences);
4 = M-Mbulge for galaxies with known types (22625 occurrences);
5 = M-Mbulge for galaxies with unknown type (18575 occurrences);
6 = AGN/quasar excluded (21 occurrences).
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- 2MASX Source Name (JHHMMSSss+DDMMSSs)
18- 22 F5.2 [Msun] BHMass [9.15/10.32] SMBH Mass
24- 29 F6.2 Mpc Dist [17.2/563] Galaxy Distance
31- 36 F6.2 --- SRN [7.9/240.1] Mean signal to noise ratio
of the tentative binary
38- 41 F4.2 --- Qlim2.75nhz [0.15/1] 95% upper limit on the mass
ratio at frequency 2.75nHz
43- 46 F4.2 --- Qlim3.475nhz [0.06/1] 95% upper limit on the mass
ratio at frequency 3.475nHz
48- 51 F4.2 --- Qlim4.2nhz [0.05/1] 95% upper limit on the mass
ratio at frequency 4.2nHz
53- 56 F4.2 --- Qlim4.925nhz [0.04/1] 95% upper limit on the mass
ratio at frequency 4.925nHz
58- 61 F4.2 --- Qlim5.65nhz [0.02/1] 95% upper limit on the mass
ratio at frequency 5.65nHz
63- 66 F4.2 --- Qlim6.375nhz [0.01/1] 95% upper limit on the mass
ratio at frequency 6.375nHz
68- 71 F4.2 --- Qlim7.1nhz [0.02/1] 95% upper limit on the mass
ratio at frequency 7.1nHz
73- 76 F4.2 --- Qlim7.825nhz [0.01/1] 95% upper limit on the mass
ratio at frequency 7.825nHz
78- 81 F4.2 --- Qlim8.55nhz [0.01/1] 95% upper limit on the mass
ratio at frequency 8.55nHz
83- 86 F4.2 --- Qlim9.275nhz [0.01/1] 95% upper limit on the mass
ratio at frequency 9.275nHz
88- 91 F4.2 --- Qlim10nhz [0.01/1] 95% upper limit on the mass
ratio at frequency 10nHz
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 12-Dec-2022