J/ApJS/282/26 Cataclysmic variables from DESI DR1 sp. (Hou+, 2026)
Spectroscopic identification and population properties of cataclysmic variables
from DESI DR1.
Hou W., Lin J.-M., Luo A.-L., Dai Z.-B., Dong Y.-Q., Ma S.-G.
<Astrophys. J. Suppl. Ser., 282, 26 (2026)>
=2026ApJS..282...26H 2026ApJS..282...26H
ADC_Keywords: Stars, variable; Spectra, optical; Magnitudes, absolute; Colors;
Novae
Keywords: Cataclysmic variable stars ; Spectroscopy ; Photometry ;
White dwarf stars ; Dwarf novae ; AM Herculis stars
Abstract:
We present a systematic search for cataclysmic variables (CVs) using
spectroscopic data from Data Release 1 of the Dark Energy
Spectroscopic Instrument. Applying the Bagging-TopPush algorithm, we
identified 433 CV candidates and related objects, of which 412 are
confirmed CVs including 76 new systems. Subtypes were assigned through
a combination of DESI spectra, Gaia data, and light curves from
time-domain surveys, revealing populations of dwarf novae, novalike
variables, magnetic CVs, and AM CVn binaries. Orbital periods were
constrained from eclipsing light curves and DESI radial velocity
curves for 14 systems. For 31 WZ Sge-type dwarf novae, we estimated
white dwarf masses and radii by combining Galaxy Evolution Explorer
ultraviolet photometry with DESI optical spectra, obtaining average
values of 0.82M☉ for mass and 13452K for effective temperature.
We also calculated the strength of the magnetic field for three polars
based on the cyclotron features. Furthermore, we derived
subtype-dependent space densities and found values consistent, within
uncertainties, with those inferred from Sloan Digital Sky Survey,
Gaia, and other survey data, though remaining lower than theoretical
predictions by 1-2 orders of magnitude. Besides, we highlight several
notable objects, including newly identified AM CVn systems, eclipsing
systems in the period gap, donor-dominated binaries, and other unusual
systems of particular interest for follow-up observations.
Description:
The Dark Energy Spectroscopic Instrument (DESI) is installed on the 4m
Mayall telescope at Kitt Peak and can collect up to 5000 spectra at
once using 10 petals, each with 500 fibers that cover a 3.2°
diameter view.
The fibers feed 10 identical spectrographs with three cameras labeled
B (3600-5800Å), R (5760-7620Å), and Z (7520-9824Å), providing
a resolution (R=λ/Δλ) from 2000 to 5500 based on
wavelength.
The DESI survey's Data Release 1 (DR1), available from 2025 March 19,
includes the initial 13 months of main-survey data. DR1 comprises over
18.7 million unique spectra, with about 13.1 million galaxies,
1.6 million quasars, and four million stars observed from 2021 May to
2022 June. Besides raw and processed spectroscopic data, a series of
value-added catalogs have been released along with DR1. Notably, the
Milky Way Survey (MWS) catalog holds 6,372,607 coadded spectra in total.
In our cataclysmic variable (CV) search, we utilize all (MWS) spectra
in DR1, including those identified as galaxies, since CV spectra often
show strong emission lines similar to those of emission-line galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 128 433 Newly identified CVs from DESI DR1
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See also:
B/cb : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2004)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
V/113 : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2003)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
V/161 : DESI DR1 redshift catalog (DESI Col.+ 2025)
J/AJ/142/181 : CVs from SDSS. VIII. The final year (Szkody+, 2011)
J/MNRAS/429/2143 : Hidden population of AM CVns in the SDSS (Carter+, 2013)
J/MNRAS/443/3174 : 72 faint CV candidates in CRTS (Breedt+, 2014)
J/MNRAS/441/1186 : Cataclysmic variables from CRTS (Drake+, 2014)
J/ApJ/901/93 : Atmosphere of hot WDs from SDSS DR12 (Bedard+, 2020)
J/AJ/159/43 : CVs from LAMOST survey. I. (Hou+, 2020)
J/AJ/159/198 : CVs in ZTF 1st-yr (2018-2019) (Szkody+, 2020)
J/ApJS/257/65 : Cataclysmic variables from LAMOST DR6 (Sun+, 2021)
J/MNRAS/513/2719 : Stellar parameters study with SED fit algo (Vines+, 2022)
J/AJ/165/148 : Sp. identified CVs from LAMOST. II. (Hou+, 2023)
J/MNRAS/524/4867 : CVs from SDSS (Inight+, 2023)
J/A+A/669/A104 : Stellar parameters from Gaia DR3 (Kordopatis+, 2023)
J/MNRAS/536/1057 : CVs from SDSS-V (Inight+, 2025)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- ID DESI survey target identifier
21- 30 A10 --- Name Target name (JHHMM+DDMM)
32 A1 --- f_Name [p] p=Notable system detailed in Section 4.1;
flag added by CDS
34- 43 F10.6 deg RAdeg Right Ascension (J2000)
45- 54 F10.6 deg DEdeg [-26/83.8] Declination (J2000)
56- 67 A12 --- OType CV subtype (1)
69- 79 F11.9 d Period [0.007/1.5]? Orbital period
81 A1 --- f_Period Flag on Period (2)
83- 87 F5.2 mag Gmag [12.2/21]? Mean Gaia DR3 G band magnitude
89- 92 F4.2 mag e_Gmag [0/0.1]? Uncertainty in Gmag
94- 98 F5.2 mag Bp-Rp [-0.57/4.1]? Mean Gaia (Blue-Red) color
100-104 I5 pc Dist [73/21721]? Distance
106-110 I5 pc e_Dist [0/13796]? Uncertainty in Dist
112-116 F5.3 mag E(B-V) [0/0.24]? The (B-V) color excess from 3D
extinction map
118-122 F5.2 mag GMag [2.3/14.7]? Absolute Gaia G band magnitude
124-128 F5.2 mag e_GMag [0.01/13.4]? Uncertainty in GMag
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Note (1): CV subtype (see section 3.1) as follows:
AM CVn = AM CVn system (12 occurrences)
CV = Cataclysmic variable (32 occurrences)
DN = Dwarf nova (44 occurrences)
IP = intermediate polar (DQ Her star; 6 occurrences)
MCV = Magnetic CV (20 occurrences)
NL = Novalike variable (21 occurrences)
Nova = Nova (3 occurrences)
Polar = Polar (AM Her star; 30 occurrences)
UG = U Gem star (80 occurrences)
UGER = ER UMa-type star (2 occurrences)
UGSU = SU UMa star (101 occurrences)
UGWZ = WZ Sge star (57 occurrences)
UGZ = Z Cam star (3 occurrences)
VY = VY Scl star (1 occurrence)
hotsub_candi = hot subdwarf (sdB/sdO) binary candidates (2 occurrences)
pre_CV = pre-CV system (Section 4.2; 19 occurrences)
Note (2): Flag on period as follows:
* = a superhump period;
: = orbital period remains uncertain.
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History:
From electronic version of the journal
License: CC-BY-4.0
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 21-Jul-2026