Swift observation and continued optical brightening of Nova Sgr 2020 No. 2 = ASASSN-20ga = PGIR20dsv

ATel #13804; K. V. Sokolovsky, E. Aydi, L. Chomiuk, A. Kawash, J. Strader (MSU), K. Mukai (NASA/GSFC), F. J. Hambsch (CBA), T. Vanmunster (CBA), S. Korotkiy (Ka-Dar Obs./Astrovert), A. Beloushkin (Voronezh)
on 15 Jun 2020; 01:52 UT
Credential Certification: Kirill Sokolovsky (kirx@scan.sai.msu.ru)

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The near-infrared (J=11.16) transient PGIR20dsv was discovered on 2020-06-01 UT by the Palomar Gattini-IR survey (De et al. 2020, PASP, 132, 1008) and spectroscopically confirmed as a classical nova (ATel #13790). It was independently found in optical band by ZTF (Masci et al. 2018, PASP, 131, 995) on 2020-05-31.418 at g=15.80 and ASAS-SN (Shappee et al. 2014, ApJ, 788, 48) on 2020-06-02.259 at g=15.3. Follow-up photometry by the AAVSO observers and the NMW survey (Sokolovsky et al. 2014, ASPC, 490, 395) shows the nova is gradually brightening in the optical band reaching the unfiltered magnitude with V zero-point CV=12.19 on 2020-06-13.946.

We observed PGIR20dsv with Swift for 0.2ks on 2020-06-13.229. No X-ray source was detected by Swift/XRT with a one sigma upper limit of 0.0006 cts/s. Assuming power law emission with the photon index of 2 and HI column density of 4.59x10^21 cm^-2 (Kalberla et al. 2005 A&A, 440, 775) this translates to the unabsorbed 0.3-10 keV flux limit of 4.5x10^-14 ergs/cm^2/s.

Swift/UVOT detected PGIR20dsv at the optical magnitude V=13.44 +/-0.03 (Vega system). We also use the Swift/UVOT image to measure the nova astrometric position relative to UCAC3 (Zacharias et al. 2010, AJ, 139, 2184) stars in the field of view: 18:22:45.32 -19:36:02.3 +/-0.2" J2000

We thank the Neil Gehrels Swift Observatory team and PI, Brad Cenko, for scheduling these ToO observations. We thank the AAVSO observers CKB, FRIB, OAAA, HDHA, TYS for their valuable contributions.