ZTF discovered AT2022lnd on MJD 59729.37 (2022-05-30.37), and we independently detected it in Pan-STARRS on MJD 59731.34 (2022-06-01.34). The combined ATLAS, Pan-STARRS and ZTF forced photometry shows a blue transient, with a two-day rise followed by a rapid fade. The last deep non-detection by ZTF occurred on MJD 59726.40 (2022-05-27.40). AT2022lnd is coincident (within 0.7") with what appears to be an extended and faint blue host object (see AstroNote #2022-121).
A spectrum was obtained on MJD 59735.95 (2022-06-05.95) with the ALFOSC instrument at the 2m Nordic Optical Telescope revealing a featureless blue continuum. Further data were taken on MJD 59737.41 (2022-06-07.41) with the GMOS on the Gemini-N telescope using the R400 grating and the GG455 blocking filter. This higher S/N spectrum revealed double-peaked H-alpha and He-I (6678A) emission lines at rest wavelength, indicating that AT2022lnd is of Galactic origin. The lines are intrinsically very weak and not visible above the noise of the NOT spectrum. The double-peaked nature of the emission lines is likely due to a dwarf nova accretion disc.
The transient peaked in the Pan-STARRS w-band on MJD 59731.36 (2022-06-01.36) with m_w= 18.59 +/- 0.01. We followed up the transient on MJD 59733.43 (2022-06-03.43) measuring m_w = 19.21 +/-0.01, suggesting an initial decline rate of ~0.3 mag per day. Subsequent follow-up over the next five days revealed a consistantly fast-fading and blue transient; with m_r = 19.83 +/- 0.11, r-z = -0.22 +/- 0.20 and a decline rate of ~0.2 mag per day on MJD 59738.34 (2022-06-08.34).
We conclude that AT2022lnd is a CV, with a more rapid decline rate than the typical 0.1 mag per day, and the extended nature of the host object is most likely due to a stellar blend.
Catalog | Name | Reported RA | Reported DEC | Reported Obj-Type | Reported Redshift | Host Name | Host Redshift | Remarks | TNS RA | TNS DEC | TNS Obj-Type | TNS Redshift |
---|---|---|---|---|---|---|---|---|---|---|---|---|
TNS | 2022lnd [ZTF22aalwamk] | 15:01:10.232 | -06:50:36.25 | CV | 0 | 15:01:10.232 | -06:50:36.25 | CV |
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