J/MNRAS/402/2369 Kinematics of young associations/clusters (Tetzlaff+, 2010)
Kinematics of young associations and clusters within 3kpc from the Sun.
Tetzlaff N., Neuhaeuser R., Hohle M.M., Maciejewski G.
<Mon. Not. R. Astron. Soc. 402, 2369 (2010)>
=2010MNRAS.402.2369T 2010MNRAS.402.2369T
ADC_Keywords: Associations, stellar ; Pulsars ; Space velocities ;
Keywords: stars: kinematics - pulsars: individual: PSR B1929+10 -
pulsars: individual: RX J1856.5-3754 -
pulsars: individual: RX J0720.4-3125 -
pulsars: individual: RX J1605.3+3249 - pulsars: individual: RBS 1223
Abstract:
Young isolated radio-quiet neutron stars are still hot enough to be
detectable at X-ray and optical wavelengths due to their thermal
emission and can hence probe cooling curves. An identification of
their birth sites can constrain their age.
For that reason, we try to identify the parent associations for four
of the so-called Magnificent Seven neutron stars for which proper
motion and distance estimates are available. We are tracing back in
time each neutron star and possible birth association centre to find
close encounters. The associated time of the encounter expresses the
kinematic age of the neutron star which can be compared to its
characteristic spin-down age. Owing to observational uncertainties in
the input data, we use Monte Carlo simulations and evaluate the
outcome of our calculations statistically.
RX J1856.5-3754 most probably originated from the Upper Scorpius
association about 0.3Myr ago. RX J0720.4-3125 was either born in the
young local association TW Hydrae about 0.4Myr ago or in Trumpler 10
0.5Myr in the past. Also RX J1605.3+3249 and RBS 1223 seem to come
from a nearby young association such as the Scorpius-Centraurus
complex or the extended Corona-Australis association. For RBS 1223
also a birth in Scutum OB2 is possible.
We also give constraints on the observables as well as on the radial
velocity of the neutron star. Given the birth association, its age and
the flight time of the neutron star, we estimate the mass of the
progenitor star. Some of the potential supernovae were located very
nearby (<100pc) and thus should have contributed to the 10Be and 60Fe
material found in the Earth's crust. In addition, we reinvestigate the
previously suggested neutron star/runaway pair PSR B1929+10/zeta
Ophiuchi and conclude that it is very likely that both objects were
ejected during the same supernova event.
Description:
Given a distance of 1kpc and typical neutron star velocities of
100-500km/s (Arzoumanian et al. 2002ApJ...568..289A 2002ApJ...568..289A; Hobbs et al.,
2005, Cat. J/MNRAS/360/974) and maximum ages of 5Myr for neutron
stars to be detectable in the optical (see cooling curves in Gusakov
et al. 2005MNRAS.363..555G 2005MNRAS.363..555G and Popov, Grigorian & Blaschke 2006, Phys.
Rev. C, 74, 025803), we restricted our search for birth associations
and clusters of young nearby neutron stars to within 3kpc. We chose a
sample of OB associations and young clusters (we use the term
`association' for both in the following) within 3kpc from the Sun with
available kinematic data and distance. We collected those from Dambis,
Mel'nik & Rastorguev (2001AstL...27...58D 2001AstL...27...58D) and Hoogerwerf
(2001A&A...365...49H 2001A&A...365...49H) and associations to which stars from the
Galactic O-star catalogue from Maiz-Apellaniz et al. (2004, Cat.
J/ApJS/151/103) are associated with. Furthermore, we added young
local associations (YLA) from Fernandez, Figueras & Torra
(2008A&A...480..735F 2008A&A...480..735F) since they are possible hosts of a few SNe in
the near past. We also included the Hercules-Lyrae association
(Her-Lyr) and the Pleiades and massive star-forming regions (Reipurth
2008, ASP Monograph Publ. Vol. 4 and Vol. 5). We set the lower limit
of the association age to 2Myr to account for the minimum lifetime of
a progenitor star that can produce a neutron star (progenitor mass
smaller than 30M☉ see e.g. Heger et al. 2003ApJ...591..288H 2003ApJ...591..288H).
The list of all explored associations and their properties can be
found in Appendix A. Coordinates as well as heliocentric velocity
components are given for a right-handed coordinate system with the
x-axis pointing towards the galactic centre and y is positive in the
direction of galactic rotation.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
assoc.dat 127 140 Positional and kinematical data for OB
associations and clusters (table A1 in the paper)
refs.dat 178 78 References
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See also:
J/AN/328/889 : Mean Radial Velocities of open clusters (Kharchenko+, 2007)
J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999)
Byte-by-byte Description of file: assoc.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [1/140] Sequential number
5- 16 A12 --- Name Name of association/cluster
17 A1 --- n_Name Note on Name (1)
19- 24 F6.2 deg GLON Galactic longitude
26- 31 F6.2 deg GLAT Galactic latitude
33- 37 F5.2 mas Plx Parallax
39- 43 F5.1 km/s UVel Heliocentric U velocity
45- 48 F4.1 km/s e_UVel ?=- Standard deviation of UVel
50- 54 F5.1 km/s VVel Heliocentric V velocity
56- 59 F4.1 km/s e_VVel ?=- Standard deviation of VVel
61- 65 F5.1 km/s WVel Heliocentric W velocity
67- 70 F4.1 km/s e_WVel ?=- Standard deviation of WVel
72 A1 --- l_Age Limit flag on Age
73- 77 F5.1 Myr Age Association/cluster age (or lower value if
interval) from the literature
78 A1 --- --- [-]
79- 83 F5.1 Myr Ageu ? Association/cluster upper interval age
value from the literature
84 A1 --- n_Age [jk] Note on Age (2)
86- 88 I3 pc Ext Extension (diameter) of association/cluster
from the literature
90-127 A38 --- Ref References given in refs.dat file
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Note (1): Notes as follows:
a = Radial velocity from Mel'nik and Efremov (1995AstL...21...10M 1995AstL...21...10M),
proper motion components derived from Humphreys (1978ApJS...38..309H 1978ApJS...38..309H)
members as median ± average deviation from median
b = Proper motion components and radial velocity derived from
Westerlund (1963MNRAS.127...71W 1963MNRAS.127...71W) members as median ± average
deviation from median
c = Coordinates and parallax denote the mean of Cas-Tau members given
by de Zeeuw et al. (1999AJ....117..354D 1999AJ....117..354D), velocity components
reflect their median U, V, W
d = Proper motion components and radial velocity derived from
Carpenter and Hodapp (2008, "The Monoceros R2 Molecular Cloud"
p. 899) members as median ± average deviation from median
e = Velocity components were derived from radial velocity only
f = Proper motion components and radial velocity derived from
Humphreys (1978ApJS...38..309H 1978ApJS...38..309H) members as median ± average
deviation from median
g = Proper motion components and radial velocity derived from
Whittet et al. (1997A&A...327.1194W 1997A&A...327.1194W) members as median ±
average deviation from median
h = Radial velocity derived from WEBDA http://www.univie.ac.at/webda
members as median ± average deviation from median.
i = Proper motion components and radial velocity derived from
Mas01 members;
proper motion (2 stars): mean proper motion maximum
deviation, radial velocity: for only one star available
(without deviation).
Note (2): Notes on Age as follows:
j = We derived ages from HR diagrams from memberlists either from
Humphreys (1978ApJS...38..309H 1978ApJS...38..309H) or Garmany and Stencel
(1992A&AS...94..211G 1992A&AS...94..211G) (Morgan et al. (1953ApJ...118..318M 1953ApJ...118..318M) for
Cyg OB4, Graham (1971AJ.....76.1079G 1971AJ.....76.1079G) for Mon OB3) by fitting a
set of theoretical Padova isochrones (Girardi et al.,
2002A&A...391..195G 2002A&A...391..195G) assuming solar metallicity. The fitting
algorithm is based on the least-squares method and uses
stellar magnitudes as weights
k = Ori OB1a: 11Myr, Ori OB1b: 2Myr, Ori OB1c: 5-11Myr,
Ori OB1d (Trapezium cluster): ∼1Myr
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Byte-by-byte Description of file:refs.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- Ref Reference code
8- 26 A19 --- BibCode BibCode
28- 48 A21 --- Aut Author's name
50-178 A129 --- Com Comments
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Acknowledgements:
Nina Tetzlaff, nina(at)astro.uni-jena.de
References:
Fernandez et al., 2008A&A...480..735F 2008A&A...480..735F
Dambis et al., 2001AstL...27...58D 2001AstL...27...58D
(End) Nina Tetzlaff [AIU Jena], Patricia Vannier [CDS] 09-Mar-2010