Sziasztok!
Ez micsoda?
Az ATEL-ben azt írják, hogy "2008S-like transient in NGC 5775". Másutt
viszont azt írják, hogy "low-luminosity Type IIn ´supernova impostors´
like SN 2008S".
Akkor ez most "szupernóva imposztor" vagy mi a bánat? Vagy csak nem
alakult még ki rá egységes elnevezés?
* * *
http://www.astronomerstelegram.org/?read=4004
Discovery of a 2008S-like transient in NGC 5775
We report the discovery of a 2008S-like transient in Catalina Sky Survey
(CSS) data taken on Mar. 27.49 UT and analyzed by the CRTS Supernova
Hunt project. The new object, identified as PSN J14535395+0334049
(SNhunt120), is located in the nearby (d=26.9 Mpc; NED) galaxy NGC 5775,
at RA: 14:53:53.95, Dec: +03:34:04.9. The objects was detected at V
=18.7 and was not seen in CSS data taken on Mar. 17.39 UT to V > 19.5.
We obtained unfiltered follow-up observations on Mar. 28.07 and the
object was observed at mag 18.5. The current absolute magnitude when
corrected for Av=0.2 is Mv=-13.9.
An optical spectrum was taken using WFCCD mounted on the du Pont 2.5m
telescope at Las Campanas Observatory on Mar 28.16 UT. The spectrum is
dominated by relatively narrow and strong Balmer lines in emission. The
H-alpha line can be well-fit by a Lorentzian profile with FWHM ~ 650
km/s. Other emission lines present in the spectrum are [Ca II] doublet
and Ca II IR triplet. The spectrum also shows strong Ca II H&K doublet
and Na I D in absorption. The EW of the Na I D feature is 2.6 Angstroms.
All these features resemble the early-time spectra of the intermediate
luminosity optical transients SN 2008S (e.g., Botticella et al. 2009)
and NGC300 2008-OT (e.g., Bond et al. 2009). The observed absolute
magnitude of the transient is consistent with the transient being
similar to these events.
The host galaxy is covered by deep archival HST data (PI Rossa; prop
10416). We encourage follow-up high precision astrometry to enable
searches for a possible progenitor.
--
Fidusz (FIDRICH Robert)
drotlevel:fidusz@zpok.hu
#jabber/gtalk: fidusz@jabber.hu
#skype: fidusz