J/A+A/650/A157 Dolidze 25 Chandra/ACIS-I X-ray sources (Guarcello+, 2021)
Dispersion timescale of protoplanetary disks in the low-metallicity young
cluster Dolidze 25.
Guarcello M.G., Biazzo K., Drake J.J., Micela G., Prisinzano L.,
Sciortino S., Damiani F., Flaccomio E., Neiner C., Wright N.J.
<Astron. Astrophys. 650, A157 (2021)>
=2021A&A...650A.157G 2021A&A...650A.157G (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; X-ray sources ; Photometry, UBVRI ;
Photometry, SDSS ; Photometry, infrared
Keywords: techniques: photometric - protoplanetary disks - stars: formation -
stars: pre-main sequence - X-rays: stars -
open clusters and associations: individual: Dolidze 25
Abstract:
The dispersal of protoplanetary disks sets the timescale available for
planets to assemble, and thus it is one of the fundamental parameters
in theories of planetary formation. Disk dispersal is determined by
several properties of the central star, the disk itself, and the
surrounding environment. In particular, the metallicity of disks may
impact their evolution, even if to date controversial results exist:
in low-metallicity clusters disks seem to rapidly disperse, while in
the Magellanic Clouds some evidence supports the existence of
accreting disks few tens of Myrs old. In this paper we study the
dispersal timescale of disks in Dolidze 25, the young cluster in
proximity of the Sun with lowest metallicity, with the aim of
understanding whether disk evolution is impacted by the
low-metallicity of the cluster. We have analyzed Chandra/ACIS-I
observations of the cluster and combined the resulting source catalog
with existing optical and infrared catalogs of the region. We selected
the disk-bearing population in a 1 degree circular region centered on
Dolidze∼25 from criteria based on infrared colors, and the disk-less
population within a smaller central region among the X-ray sources
with OIR counterpart. In both cases, criteria are applied to discard
contaminating sources in the foreground/background. We have derived
stellar parameters from isochrones fitted to color-magnitude diagrams.
We derived a disk fraction of about 34% and a median age of the
cluster of 1.2Myrs. To minimize the impact of incompleteness and
spatial inhomogeneity of the list of members, we restricted this
calculation to stars in a magnitude range where our selection of
cluster members is fairly complete and by adopting different cuts in
stellar masses. By comparing this estimate with existing estimates of
the disk fraction of clusters younger than 10Myrs, our study suggests
that the disk fraction of Dolidze 25 is lower than what is expected
from its age alone. Even if our results are not conclusive given the
intrinsic uncertainty on stellar ages estimated from isochrones
fitting to color-magnitude diagrams, we suggest that disk evolution in
Dolidze 25 may be impacted by the environment. Given the poor O star
population and low stellar density of the cluster, it is more likely
that disks dispersal timescale is dictated more by the low metallicity
of the cluster rather than external photoevaporation or dynamical
encounters.
Description:
These two tables contain the X-ray sources detected in a 150ksec
observation with Chandra/ACIS-I centered on the young stellar cluster
Dolidze 25 and the list of young stars associated with the cluster and
the surrounding nebula. Members are selected from the detection in the
X-ray observation, infrared excesses, and spectroscopic
classification.
Objects:
----------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------
06 45 06 +00 18.0 Dolidze 25 = Cl Dolidze 25
----------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
xsources.dat 487 615 X-ray sources detected in a 150ks observation
with Chandra/ACIS-I centered on the young
stellar cluster Dolidze 25
members.dat 828 1097 Members, selected from detection in the X-ray
observation, infrared excesses, and
spectroscopic classification
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See also:
B/corot : CoRoT observation log (N2-4.4) (CoRoT 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/321 : IPHAS DR2 Source Catalogue (Barentsen+, 2014)
II/341 : VPHAS+ DR2 survey (Drew+, 2016)
II/328 : AllWISE Data Release (Cutri+ 2013)
II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)
J/A+A/509/A104 : UBVRIJHK photometry of Dolidze 25 (Delgado+, 2010)
Byte-by-byte Description of file: xsources.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- ID [0/1008] Stellar ID in the members catalog
(MEMBER_ID)
6- 23 A18 --- ACIS X-ray identifier (ACIS_DES)
25- 42 F18.14 deg RAdeg Right Ascension (J2000) (RA)
44- 62 F19.17 deg DEdeg Declination (J2000) (DEC)
64- 66 I3 ct ctB Counts in the broad band (COUNTS_B)
68- 70 I3 ct ctS Counts in the soft band (COUNTS_S)
72- 74 I3 ct ctH Counts in the hard band (COUNTS_H)
76- 94 F19.16 arcmin offAngle Off-axis angle (OFFAXIS_ANGLE)
96-105 F10.5 pix+2 SrcArea Average aperture area for merged
observations (SRC_AREA)
107-114 F8.6 --- PSFFrac Average PSF fraction at 1.5keV for merged
observations (PSF_FRAC)
116-126 E11.8 --- ProbKS ? Smallest p-value for the non-variable
null hypothesis (PROB_KS)
128-145 F18.14 cm+2/ct meanARFB Mean effective area in the broad band
(MEANARFB)
147-164 F18.14 cm+2/ct meanARFS Mean effective area in the soft band
(MEANARFS)
166-183 F18.14 cm+2/ct meanARFH Mean effective area in the hard band
(MEANARFH)
185-187 I3 ct BkgCtsB Counts in the background area in the broad
band (BKGCNTSB)
189-190 I2 ct BkgCttsS Counts in the background area in the soft
band (BKGCNTSS)
192-194 I3 ct BkgCtsH Counts in the background area in the hard
band (BKGCNTSH)
196-216 F21.16 --- BkgScalB Background scaling factor in the broad band
(BACKSCAL_B)
218-238 F21.16 --- BkgScalS Background scaling factor in the soft band
(BACKSCAL_S)
240-260 F21.16 --- BkgScalH Background scaling factor in the hard band
(BACKSCAL_H)
262-272 F11.7 ct NetctB Net counts in the broad band (NETCNTSB)
274-286 F13.9 ct NetctS ? Net counts in the soft band (NETCNTSS)
288-301 F14.10 ct NetctH ? Net counts in the hard band (NETCNTSH)
303-312 F10.7 ct E_NetctB 1 sigma upper bound of the net counts in
the broad band (NETCNTSSIGMAUP_B)
314-323 F10.7 ct E_NetctS 1 sigma upper bound of the net counts in
the soft band (NETCNTSSIGMAUP_S)
325-334 F10.7 ct E_NetctH 1 sigma upper bound of the net counts in
the hard band (NETCNTSSIGMAUP_H)
336-345 F10.7 ct e_NetctB 1 sigma lower bound of the net counts in
the broad band (NETCNTSSIGMALO_B)
347-357 F11.8 ct e_NetctS ? 1 sigma lower bound of the net counts in
the soft band (NETCNTSSIGMALO_S)
359-369 F11.8 ct e_NetctH ? 1 sigma lower bound of the net counts in
the hard band (NETCNTSSIGMALO_H)
371-383 E13.10 [-] logPBSB Log(10) p-value for the null-hypothesis of
no source in the broad band (PBS_B)
385-397 E13.10 [-] logPBSS Log(10) p-value for the null-hypothesis of
no source in the soft band (PBS_S)
399-412 E14.10 [-] logPBSH Log(10) p-value for the null-hypothesis of
no source in the hard band (PBS_H)
414-426 E13.8 ph/cm+2/s phFluxB Photons flux in the broad band (PHOTFLUX_B)
428-440 E13.8 ph/cm+2/s phFluxS ? Photons flux in the soft band (PHOTFLUX_S)
442-454 E13.8 ph/cm+2/s phFluxH ? Photons flux in the hard band (PHOTFLUX_H)
456-465 F10.8 keV EMed Median photon energy (ENERMED)
467-476 F10.8 keV EQ25 25th percentile of the photon energy
distribution (ENERQ25)
478-487 F10.8 keV EQ75 75th percentile of the photon energy
distribution (ENERQ75)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: members.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- ID [1/1097] Stellar ID (ID)
6- 23 F18.14 deg RAdeg Right Ascension (J2000) (RA)
25- 46 E22.18 deg DEdeg Declination (J2000) (DEC)
48- 52 F5.2 mag umagVP ? VPHAS/DR2 u band magnitude (MAGU_VP)
54- 57 F4.2 mag e_umagVP ? Error of the VPHAS/DR2 u band magnitude
(ERRMAGU_VP)
59- 63 F5.2 mag gmagVP ? VPHAS/DR2 g band magnitude (MAGG_VP)
65- 68 F4.2 mag e_gmagVP ? Error of the VPHAS/DR2 g band magnitude
(ERRMAGG_VP)
70- 74 F5.2 mag HamagVP ? VPHAS/DR2 Halpha band magnitude (MAGHA_VP)
76- 79 F4.2 mag e_HamagVP ? Error of the VPHAS/DR2 Halpha band magnitude
(ERRMAGHA_VP)
81- 85 F5.2 mag rmagVP ? VPHAS/DR2 r band magnitude (MAGR_VP)
87- 90 F4.2 mag e_rmagVP ? Error of the VPHAS/DR2 r magnitude
(ERRMAGR_VP)
92- 96 F5.2 mag imagVP ? VPHAS/DR2 i band magnitude (MAGI_VP)
98-101 F4.2 mag e_imagVP ? Error of the VPHAS/DR2 i band magnitude
(ERRMAGI_VP)
103-107 F5.2 mag rmagIP ? IPHAS/DR2 r band magnitude (MAGR_IP)
109-112 F4.2 mag e_rmagIP ? Error of the IPHAS/DR2 r band magnitude
(ERRMAGR_IP)
114-118 F5.2 mag imagIP ? IPHAS/DR2 i band magnitude (MAGI_IP)
120-123 F4.2 mag e_imagIP ? Error of the IPHAS/DR2 i band magnitude
(ERRMAGI_IP)
125-129 F5.2 mag HamagIP ? IPHAS/DR2 Halpha band magnitude (MAGHA_IP)
131-134 F4.2 mag e_HamagIP ? Error of the IPHAS/DR2 Halpha magnitude
(ERRMAGHA_IP)
136-142 F7.4 mag gmagPAN ? Pan-STARRS g band magnitude (MAGG_PAN)
144-149 E6.4 mag e_gmagPAN ? Error of the Pan-STARRS g band magnitude
(ERRMAGG_PAN)
151-157 F7.4 mag rmagPAN ? Pan-STARRS r band magnitude (MAGR_PAN)
159-164 E6.4 mag e_rmagPAN ? Error of the Pan-STARRS r band magnitude
(ERRMAGR_PAN)
166-172 F7.4 mag imagPAN ? Pan-STARRS i band magnitude (MAGI_PAN)
174-179 E6.4 mag e_imagPAN ? Error of the Pan-STARRS i band magnitude
(ERRMAGI_PAN)
181-187 F7.4 mag zmagPAN ? Pan-STARRS z band magnitude (MAGZ_PAN)
189-194 E6.4 mag e_zmagPAN ? Error of the Pan-STARRS z band magnitude
(ERRMAGZ_PAN)
196-202 F7.4 mag ymagPAN ? Pan-STARRS y band magnitude (MAGY_PAN)
204-209 E6.4 mag e_ymagPAN ? Error of the Pan-STARRS y band magnitude
(ERRMAGY_PAN)
211-219 F9.6 mag UmagDEL ? U band magnitude from Delgado et al.
(2010A&A...509A.104D 2010A&A...509A.104D) (MAGU_DEL)
221-231 F11.9 mag e_UmagDEL ? Error of the U band magnitude from Delgado
et al. (2010A&A...509A.104D 2010A&A...509A.104D) (ERRMAGU_DEL)
233-241 F9.6 mag BmagDEL ? B band magnitude from Delgado et al.
(2010A&A...509A.104D 2010A&A...509A.104D) (MAGB_DEL)
243-253 F11.9 mag e_BmagDEL ? Error of the B band magnitude from Delgado
et al. (2010A&A...509A.104D 2010A&A...509A.104D) (ERRMAGB_DEL)
255-259 F5.2 mag VmagDEL ? V band magnitude from Delgado et al.
(2010A&A...509A.104D 2010A&A...509A.104D) (MAGV_DEL)
261-264 F4.2 mag e_VmagDEL ? Error of the V band magnitude from Delgado
et al. (2010A&A...509A.104D 2010A&A...509A.104D) (ERRMAGV_DEL)
266-274 F9.6 mag RmagDEL ? R band magnitude from Delgado et al.
(2010A&A...509A.104D 2010A&A...509A.104D) (MAGR_DEL)
276-286 F11.9 mag e_RmagDEL ? Error of the R band magnitude from Delgado
et al. (2010A&A...509A.104D 2010A&A...509A.104D) (ERRMAGR_DEL)
288-296 F9.6 mag ImagDEL ? I band magnitude from Delgado et al.
(2010A&A...509A.104D 2010A&A...509A.104D) (MAGI_DEL)
298-308 F11.9 mag e_ImagDEL ? Error of the I band magnitude from Delgado
et al. (2010A&A...509A.104D 2010A&A...509A.104D) (ERRMAGI_DEL)
310-319 F10.7 mag Jmag ? 2MASS or UKIDSS/DR10 J band magnitude (MAGJ)
321-328 E8.6 mag e_Jmag ? Error of the 2MASS or UKIDSS/DR10 J band
magnitude (ERRMAGJ)
330-339 F10.7 mag Hmag ? 2MASS or UKIDSS/DR10 H band magnitude (MAGH)
341-348 E8.6 mag e_Hmag ? Error of the 2MASS or UKIDSS/DR10 H band
magnitude (ERRMAGH)
350-359 F10.7 mag Kmag ? 2MASS or UKIDSS/DR10 K band magnitude (MAGK)
361-368 E8.6 mag e_Kmag ? Error of the 2MASS or UKIDSS/DR10 K band
magnitude (ERRMAGK)
370-379 F10.7 mag [3.6] ? Spitzer/IRAC [3.6] band magnitude (MAG1)
381-391 F11.9 mag e_[3.6] ? Error of the Spitzer/IRAC [3.6] band
magnitude (ERRMAG1)
393-402 F10.7 mag [4.5] ? Spitzer/IRAC [4.5] band magnitude (MAG2)
404-414 F11.9 mag e_[4.5] ? Error of the Spitzer/IRAC [4.5] band
magnitude (ERRMAG2)
416-425 F10.7 mag [5.8] ? Spitzer/IRAC [5.8] band magnitude (MAG3)
427-437 F11.9 mag e_[5.8] ? Error of the Spitzer/IRAC [5.8] band
magnitude (ERRMAG3)
439-448 F10.7 mag [8.0] ? Spitzer/IRAC [8.0] band magnitude (MAG4)
450-460 F11.9 mag e_[8.0] ? Error of the Spitzer/IRAC [8.0] band
magnitude (ERRMAG4)
462-467 F6.3 mag [3.4] ? WISE [3.4] band magnitude (MAGW1)
469-473 F5.3 mag e_[3.4] ? Error of the WISE [3.4] band magnitude
(ERRMAGW1)
475-480 F6.3 mag [4.6] ? WISE [4.6] band magnitude (MAGW2)
482-486 F5.3 mag e_[4.6] ? Error of the WISE [4.6] band magnitude
(ERRMAGW2)
488-493 F6.3 mag [12] ? WISE [12] band magnitude (MAGW3)
495-499 F5.3 mag e_[12] ? Error of the WISE [12] band magnitude
(ERRMAGW3)
501-506 F6.3 mag [22] ? WISE [22] band magnitude (MAGW4)
508-512 F5.3 mag e_[22] ? Error of the WISE [22] band magnitude
(ERRMAGW4)
514-520 E7.4 mas Plx Stellar parallaxes from Gaia/EDR3 (PARALLAX)
522-541 F20.18 mas e_Plx Error of the stellar parallaxes from Gaia/EDR3
(ERR_PARALLAX)
543 I1 --- Disk [0/1] Equal to 1 for stars with disks (DISK)
545 I1 --- XMember [0/1] Equal to 1 for disk-less members
(XMEMBER)
547 I1 --- SpMember [0/1] Equal to 1 for spectroscopic members
(SPECTR_LITER)
549-560 F12.8 mag AV Individual stellar extinction (AV)
562-574 F13.10 mag e_AV Error of the individual stellar extinction
(ERRAV)
576-584 F9.7 [Myr] logAge ? Log(10) of individual stellar age (AGE)
586-597 F12.10 [Myr] e_logAge ? Error of the Log(10) of individual stellar
age (ERRAGE)
599-608 F10.8 Msun Mass ? Individual stellar mass (MASS)
610-621 F12.10 Msun e_Mass ? Error of the individual stellar mass
623-641 A19 --- IPHAS IPHAS/DR2 stellar designation
(JHHMMSS.ss+DDMMSS.s) (VPHAS_DES)
643-669 A27 --- VPHAS VPHAS/DR2 (Cat. II/341) stellar designation
(VPHASDR2 JHHMMSS.s+DDMMSS.s) (VPHAS_DES)
671-674 I4 --- DELGADO ?=0 Delgado et al. (2010A&A...509A.104D 2010A&A...509A.104D, Cat.
J/A+A/509/A104) stellar designation
(DELGADO_DES)
676-684 I9 --- COROT ?=0 CoRoT (Cat. B/corot) stellar designation
(COROT_DES)
686-701 A16 --- TWOMASS 2MASS/PSC (Cat. II/246) stellar designation
(HHMMSSss+DDMMSSs) (TWOMASS_DES)
703-714 I12 --- UKIDSS ?=0 UKIDSS/DR10 stellar designation
(UKIDSS_DES)
716-721 I6 --- IRAC ?=0 IRAC stellar designation (IRAC_DES)
723-741 A19 --- WISE AllWISE (Cat. II/328) Source Catalog stellar
designation (JHHMMSS.ss+DDMMSS.s) (WISE_DES)
743-760 A18 --- ACIS Stellar designation in the X-ray sources
catalog (HHMMSS.ss+DDMMSS.s) (ACIS_DES)
762-789 A28 --- GaiaDR2 GAIA/DR2 (Cat. I/345) stellar designation
(Gaia DR2 NNNNNNNNNNNNNNNNNNN) (GAIADR2_DES)
791-809 I19 --- GaiaEDR3 ? GAIA/EDR3 (Cat. I/350) stellar designation
(GAIAEDR3_DES)
811-828 I18 --- PanStarrs ? Pan-STARRS (Cat. II/349) stellar designation
(PanStarrs_DES)
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Acknowledgements:
Mario Guarcello, mario.guarcello(at)inaf.it
(End) Patricia Vannier [CDS] 12-Apr-2021