J/MNRAS/518/3301 Ha-excess sources spectroscopic follow-up (Fratta+, 2023)
Spectroscopic follow-up of a sub-set of the Gaia/IPHAS catalogue of
Hα-excess sources.
Fratta M., Scaringi S., Monguio M., Pala A.F., Drew J.E., Knigge C.,
Ilkiewicz K.A., Gandhi P.
<Mon. Not. R. Astron. Soc. 518, 3301-3311 (2023)>
=2023MNRAS.518.3301F 2023MNRAS.518.3301F (SIMBAD/NED BibCode)
ADC_Keywords: Stars, emission ; Photometry, H-alpha ; Spectra, optical
Keywords: techniques: photometric - techniques: spectroscopic -
stars: emission-line, Be
Abstract:
State-of-the-art techniques to identify Ha emission line sources in
narrow- band photometric surveys consist of searching for Ha excess
with reference to nearby objects in the sky (position-based
selection). However, while this approach usually yields very few
spurious detections, it may fail to select intrinsically faint and/or
rare Ha-excess sources. In order to obtain a more complete
representation of the heterogeneous emission line populations, we
recently developed a technique to find outliers relative to nearby
objects in the colour-magnitude diagram (CMD-based selection). By
combining position -based and CMD-based selections, we built an
updated catalogue of Ha-excess candidates in the northern Galactic
Plane. Here we present spectroscopic follow-up observations and
classification of 114 objects from this catalogue, that enable us to
test our novel selection method. Out of the 70 spectroscopically
confirmed Ha emitters in our sample, 15 were identified only by the
CMD-based selection, and would have been thus missed by the classic
position-based technique. In addition, we explore the distribution of
our spectroscopically confirmed emitters in the Gaia CMD. This
information can support the classification of emission line sources in
large surveys, such as the upcoming WEAVE and 4MOST, especially if
augmented with the introduction of other colours.
Description:
Spectroscopic classification of 114 Ha-excess candidates in the
Northern Galactic Plane. The spectra were observed by the Gemini
facility via a poor-weather program. These follow-up observations are
part of a pilot program to validate the CMD-based selection of
Ha-excess sources in the Gaia/IPHAS catalogue (Scatingi et al., 2018,
Cat. IV/36). We provide the reduced spectra of the 114 classified
sources, as well as a set of astrometric and photometric information
used to support their classification.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
sources.dat 355 114 List of sources
fits/* . 114 Individual fits spectra
--------------------------------------------------------------------------------
See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
IV/36 : Gaia-IPHAS/KIS Value-Added Catalogues (Scaringi+, 2018)
J/MNRAS/505/1135 : Gaia/IPHAS catalogue of Ha-excess sources (Fratta+, 2021)
Byte-by-byte Description of file: sources.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR2 Unique Gaia DR2 source identifier
21- 39 I19 --- GaiaEDR3 Unique Gaia EDR3 source identifier
41- 60 F20.16 deg RAdeg Gaia DR2 barycentric right ascension (ICRS)
at Epoch 2015.5
62- 80 F19.16 deg DEdeg Gaia DR2 barycentric declination (ICRS)
at Epoch 2015.5
82-100 F19.17 kpc DistDR2 Parallax-inversion defined distance (Gaia DR2)
102-120 F19.17 kpc DistEDR3 Parallax-inversion defined distance (Gaia EDR3)
122-141 F20.17 mag GMAGDR2 G-band absolute magnitude (Gaia DR2)
143-162 F20.17 mag GMAGEDR3 G-band absolute magnitude (Gaia EDR3)
164-182 F19.17 mag BP-RPDR2 G(BP) - G(RP) colour (Gaia DR2)
184-191 F8.6 mag BP-RPEDR3 G(BP) - G(RP) colour (Gaia EDR3)
193-201 F9.6 mag rmag r-band magnitude (IPHAS DR2)
203-222 F20.18 mag r-i r-i colour (IPHAS DR2)
224-242 F19.17 mag r-Ha r-Ha colour (IPHAS DR2)
244-262 F19.16 --- CMDsigni Significance of Ha-excess, obtained from the
CMD-based selection (Fratta et al., 2021,
Cat. J/MNRAS/505/1135)
264-283 F20.17 --- POSsigni Significance of Ha-excess, obtained from the
position-based selection (Fratta et al., 2021,
Cat. J/MNRAS/505/1135)
285-302 F18.15 0.1nm FWHM Full width at half maximum of the Ha line
304-312 A9 --- Class Spectroscopic classification
314-355 A42 --- FileName Name of the spectrum file in subdirectory fits
--------------------------------------------------------------------------------
Acknowledgements:
Matteo Fratta, matteo.fratta(at)durham.ac.uk
(End) Patricia Vannier [CDS] 15-Nov-2022