J/AJ/170/24 Properties of new members in stellar group ASCC 127 (Wang+, 2025)
Multiple generation star formation in Cepheus Flare.
Wang F., Fang M., Fu X., Su Y., Chen X., Zhang S., Liu P., Wang X.-L.,
Tian H., Cui W., Li Z.
<Astron. J., 170, 24 (2025)>
=2025AJ....170...24W 2025AJ....170...24W
ADC_Keywords: Star Forming Region; YSOs; Positional data; Radial velocities;
Proper motions; Photometry; Optical; Extinction
Keywords: Star forming regions ; Moving clusters
Abstract:
We present an analysis of the young stellar moving group ASCC 127
using Gaia DR3 data, significantly expanding its membership to 3971
stars-double the number identified in previous studies. Using
kinematic and distance criteria, ASCC 127 is divided into five
subgroups (Groups 1-5) with ages spanning from 15 to 32 Myr. Groups
1-5 are spatially linked to the Cepheus Flare star-forming region,
revealing potential evidence of four sequential star formation
episodes at approximately 32Myr, 20Myr, 15Myr, and 7Myr. Through
dust and gas mapping, we identify a spatial cavity extending several
tens of parsecs, which may have resulted from feedback processes such
as supernovae associated with earlier generations of stars in the
region. This structure, along with the larger Loop III feature,
indicates that feedback from massive stars likely influenced the
interstellar medium (ISM). By integrating young stellar populations
with ISM studies, we provide a detailed picture of the feedback-
driven star-formation history in the Cepheus Flare region.
Description:
We integrate data from Gaia DR3 star sources, interstellar dust maps,
CO maps, and HI maps to investigate the spatial, kinematic, and ISM
properties of ASCC 127 and its surrounding environment.
In this work, we use Gaia DR3 (I/355) 5D phase-space information,
i.e., GLON, GLAT, pmGLON, pmGLAT, and distances, to identify ASCC 127
members through clustering algorithms and to estimate their kinematic
properties and ages.
Edenhofer+ (2024A&A...685A..82E 2024A&A...685A..82E) utilized distance and extinction
estimates for 54 million nearby stars derived from Gaia BP/RP spectral
data to conduct a parsec-scale three-dimensional interstellar dust
extinction map. The dust map is used to identify low-density cavities
and high-density molecular clouds associated with the Cepheus Flare.
The CO map used in this work is released from the work of
Dame+ (2001ApJ...547..792D 2001ApJ...547..792D), who combined data from 37 individual
surveys to produce a comprehensive gas map of the entire Milky Way.
These surveys were conducted using the CfA 1.2m telescope and a
similar instrument located at Cerro Tololo in Chile. The CO map traces
molecular gas distributions and kinematics, allowing us to identify
filaments and cavities in the Cepheus Flare region.
The HI4PI data set is the combined result of two high-sensitivity,
high-resolution all-sky HI 21cm surveys (J/A+A/594/A116): the
Effelsberg-Bonn HI Survey (EBHIS, J/A+A/585/A41) and the Parkes
Galactic All-Sky Survey (McClure-Griffiths+, 2009ApJS..181..398M 2009ApJS..181..398M;
Kalberla+, 2010A&A...521A..17K 2010A&A...521A..17K; Kalberla+, 2015A&A...578A..78K 2015A&A...578A..78K). The
former was conducted using the 100m Effelsberg telescope, while the
latter employed the 64m Parkes telescope. The HI map complements the
CO data by providing insights into the diffuse atomic gas component of
the ISM.
Objects:
-----------------------------------------------------------
RA (2000) DE Designation(s)
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23 09 14.29 +64 59 55.9 ASCC 127 = [KPR2005] 127
23 34 00.00 +72 00 00.0 Cepheus Flare = NAME Cep Flare
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File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 61 3971 Members of groups 1-5
table2.dat 85 5 Properties of groups 1-5
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See also:
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
VIII/73 : HI Parkes All Sky Survey Catalogue (HIPASS) (Meyer+, 2004)
VIII/89 : Northern HI Parkes All Sky Survey Catalogue (HIPASS) (Wong+, 2006)
J/ApJS/185/451 : PMS stars in the Cepheus flare region (Kun+, 2009)
J/A+A/533/A122 : Diffuse neutral hydrogen in HIPASS (Popping+, 2011)
J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)
J/A+A/585/A41 : EBHIS spectra and HI column density maps (Winkel+, 2016)
J/A+A/594/A116 : HI4PI spectra and column density maps (HI4PI team+, 2016)
J/AJ/158/122 : Local structure & star formation history of MW (Kounkel+, 2019)
J/ApJS/245/32 : Newly identified star clusters in Gaia DR2 (Liu+, 2019)
J/ApJ/885/131 : ∼200 high-mass SFR plx & proper motion with VLBI (Reid+, 2019)
J/MNRAS/505/5164 : The Gaia view of the Cepheus flare (Szilagyi+, 2021)
J/AJ/163/64 : Param. for adopted members of Corona Australis (Esplin+, 2022)
J/A+A/667/A163 : Upper Scorpius and Ophiuchus members (Miret-Roig+, 2022)
J/ApJ/931/156 : 3D morph. of open clusters with Gaia EDR3. II. (Pang+, 2022)
J/ApJ/933/77 : Temp. & luminosity of Gaia EDR3 Serpens members (Zhou+, 2022)
J/A+A/678/A71 : Cluster ages in Sco-Cen (Ratzenboeck+, 2023)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg GLON Galactic longitude
11- 19 F9.5 deg GLAT Galactic latitude
21- 24 F4.2 mas plx [1.76/3.52] Parallax
26- 30 F5.2 mas/yr pmGLON [-5.41/2.91] Proper motion in Galactic
longitude with respect to LSR
32- 36 F5.2 mas/yr pmGLAT [-2.82/2.6] Proper motion in Galactic latitude
with respect to LSR
38- 42 F5.2 mag BPmag [6.14/21.46] Apparent observed Gaia BP
magnitude
44- 48 F5.2 mag RPmag [5.21/17.92] Apparent observed Gaia RP
magnitude
50- 54 F5.2 mag Gmag [6.12/19.22] Apparent observed Gaia G
magnitude
56- 59 F4.2 mag AV [0.11/1.94] V-band extinction
61 I1 --- Grp [1/5] Group ID
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 I1 --- Grp [1/5] Group ID
3- 8 F6.2 deg GLON Median galactic longitude
10- 14 F5.2 deg GLAT Median galactic latitude
16- 18 I3 pc Dist [371/487] Median distance
20- 21 I2 pc s_Dist [21/34] Dist standard deviation
23- 25 I3 pc Xpos [35/224] Median heliocentric X position
27- 28 I2 pc s_Xpos [14/35] Xpos standard deviation
30- 32 I3 pc Ypos [306/463] Median heliocentric Y position
34- 35 I2 pc s_Ypos [22/33] Ypos standard deviation
37- 39 I3 pc Zpos [-28/34] Median heliocentric Z position
41- 42 I2 pc s_Zpos [8/40] Zpos standard deviation
44- 47 F4.1 mas/yr pmGLON [-3.7/0.8] Median proper motion in Galactic
longitude with respect to LSR
49- 51 F3.1 mas/yr s_pmGLON [0.7/1] pmGLON standard deviation
53- 56 F4.1 mas/yr pmGLAT [-0.7/0.7] Median proper motion in Galactic
latitude with respect to LSR
58- 60 F3.1 mas/yr s_pmGLAT [0.5/1] pmGLAT standard deviation
62- 65 F4.1 km/s VLSR [-7.3/-0.7] Median radial velocity with
respect to LSR
67- 69 F3.1 km/s s_VLSR [4.9/9.2] VLSR standard deviation
71- 73 I3 Msun Mass [140/800] Total mass
75- 76 I2 Myr Age [15/32] Age
78 I1 Myr e_Age [1/5] Lower uncertainty on Age
80 I1 Myr E_Age [1/4] Upper uncertainty on Age
82- 85 I4 --- Nstar [140/1194] Number of members
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History:
From electronic version of the journal
(End) Prepared by [AAS], Robin Leichtnam [CDS] 30-Mar-2026