We update the spectra of SN 2009an. The photometry shows the first early decline phase and the I-band light curve is reaching the minimum preceding secondary maximum. The spectrum at Mar. 20 began to show the NaID line at 5800A. The blueshifted SiII 6355 and CaII IR triplet line is rapidly receding with time. The observations of this object will be continued.
We update the optical spectroscopy and photometry of Type IIP SN 2008in. The light curve evolved on plateau phase, the pronounced variations is not seen. However, the spectra shows that the several small line absorptions have been rapidly formed since Feb. 20. The formation of their lines comes from heavy elements, which are synthesized near the center of core collapse explosion. Revealing these lines indicates that the layer of hydrogen expands and becomes optically thin, which suggests that the rapidly decreasing the luminosity will come soon.
We have been observed SN 2009an since Mar. 1 2009. The preliminary photometric results is shown in above figure. The approximate magnitudes of comparison star is refereed from USNO A-2.0 catalog. The luminosity would be suffered from the reddening by host galaxy. The maximum day is roughly determined as Mar. 10 from the light curve. The delta_m15(B), most important parameter for the luminosity indicator of SNe Ia, will be determined from the B-band photometry for next 10 days. We will continue the photometric and spectroscopic observations.
■ [blazar] PKS 1502+106 : The high state of the polarization degree
The figure shows the light curve and the temporal variation of the object in V band. The amplitude of the magnitude of the object was about 1.8. The object has been recently brightened since JD 2454870. The polarization degree of the object was high, simultaneously.
The figure shows the light curve and the temporal variation of the polarization degree in V band. The polarization degree of the object was high until JD 2454865 (larger than 20 %). The polarization degree of the object, however, had been reduced since JD 2454880. In JD 2454890, the object was rapidly fading from V~14.8 to 15.7.
■ [supernova] Updating the optical observations of Type II-P SN 2008ij : Coming soon decreasing the luminosity ?
We newly update the optical photometric and spectroscopic results of SN 2008ij. The photometry of this SN indicates that the brightness is clearly just evolving for the period of first plateau phase. The spectroscopic results shows that the P-Cyg profile of H_alpha decrease the velocity as time evolves. The phase of rapidly decreasing the luminosity might be come soon.
■ [supernova] Update the spectra of SN 2009an : The deep line of Oxygen and the feature of fast-expanding SNe Ia
We updated the spectra of Type Ia SN 2009an. The spectra shows the line velocity of SiII6355 declining rapidly, which means that the expanding layer of the Silicon becomes rapidly optically thin. The SiII5972 at 5800A becomes shallow with time, which means that the photospheric temprature would become low. Such a phenomenon is commonly seen in rapidly expanding SNe Ia, as HVG (Benetti et al. 2005) The OI7773 line absorption becomes deep. In general, the Oxygen line of Type Ia SN is thought to be synthesized from carbon, but there is a possibility that a line feature of the light element is the evidence of an unburnt material of the progenitor white dwarf. If the abundance of the Oxygen is rich in the layer of SN 2009an, the explosion mechanism of SNe Ia might be required to be modified. The dense photometric observations will be required. We will continue the observations of SN 2009an.
We have continued the spectroscopic observations for SN 2009an. The spectrum of SN 2009an on Mar. 1 showed the high velocity component of CaII IR triplet, but our spectrum newly obtained on Mar. 4 showed that the high velocity component of CaII receded. The observations will be continued.
■ [blazar] PKS 1502+106 : brightening
We have observed PKS 1502+106 since 9 August 2008.
The figure shows the lightcurve and Polarization degree in V band of the object.
The flux of this object has increased with the Polarization degree in these days.
The figure shows that the lightcurve and the Polarization degree in V band of this object.
There is anticorrelation between the lightcurve and the Polarization degree in a longterm tendency.
The discovery of SN 2009an was reported in CBET 1707. We reported the spectroscopic type identifications of SN 2009an in CBET 1710. We performed spectroscopic observations of SN 2009an on Mar. 1.6 UT. The spectrum is shown above figure, which was corrected for the radial velocity of the host galaxy NGC 4332. The obtained spectrum shows the typical characteristics of Type Ia supernovae at the early phase. Especially, the large blueshifted line absorption of CaII IR triplet is seen in our spectrum. The line absorption seems to be separated in the components of high and low velocity. The SiII-635.5nm line feature is blueshifted to 14,000km/s. We will continue the observations of SN 2009an.