Night Report 2015-02-26

The night was probably photometric, but we couln't get more

standard fields due to pointing restriction.

Observers : Laurent Le Guillou, Sylvain Baumont, Ayan Mitra

Support team : Pierre François Leget, Nicolas Chotard

TAT : K. Maguire, J. Polshaw

Clear sky, strong wind from North-East, 55% humidity

Moon at 2nd quarter, 65% illumination, setting at 5:20

CALIBRATIONS and WEATHER :

 - Evening : EFOSC_bias, EFOSC_FlatSpec, EFOSC_SpecArc

   - 23:30   Sunset, strong wind above 15m/s, NTT DOME stays CLOSED, no SkyFlat.

 - 03:25  The wind settled betwen 12 and 15m/s, NTT DOME OPENED.

     => Pointing restriction towards North-East, so we had to discard 

        the highest priority objects PSNJ1409+1731 and LSQ15kp. Gasp!

        We then had to select declining objects (West), and towards the South.

 - 08:10  The wind speed raised quickly to 20m/s. NTT DOME CLOSED.

 - 09:11  Astronomical twilight. End of night.

 - Morning : Dome still closed. No SkyFlat

SCIENCE OBSERVATIONS :

 - 03:33  image analysis and focus

 - 03:52  ASASSN-14ha Follow-up, Bi:2x150s VR:200s

        Airmass 2.1, seeing 1.2", 76º from the moon

 - 04:14  OGLE-2014-SN-073 Follow-up, V:3x300s Ri:2x250s

        Airmass 1.8, seeing 1.5" to 0.9", 81º from the moon

 - 04:56  Photometric Standard Field PG1047, BVRi

        57% humidity, temperature 11º, airmass 1.15

        It is at the limit of the pointing restrictions.

 - 05:05  STD LTT3864, Gr11 Gr13 Gr16, slit 1" and 1.5", airmass 1.01

 - 05:44  OGLE-2015-SN-060 Classification, Gr13:1200s, slit 1.5"

        Airmass 2.4, seeing 1.1" to 1.6", noisy spectrum

        NOTE : The OGLE finding chart (max. brigthness, the one displayed 

        in the Marshall) is wrong. The OGLE reference image is OK.

     => SN-Ia, maybe 91-T like, z ~ 0.07

 - 06:13  SNHiTS15I Classification, Gr13:1200s, slit 1.5"

        Airmass 1.3, seeing 1.5" to 2", noisy spectrum

     => Probably SN-Ia, z ~ 0.15

 - 06:43  SNHiTS15J Classification, Gr:2700s, slit 1.5"

        Airmass 1.7, seeing 2" to 1.5", noisy spectrum

        The SN is the faint trace on the left.

     => Probably SN-Ia pre-max, z_gal = 0.11

 - 07:37  SN2014ad Follow-up, Gr13:2700s, slit 1.5"

        Airmass 1.2, seeing 2" to 1.4". 

        The slit positioning was tricky, and might be inaccurate.

        We had to abort the exposure after 1874s due to wind above 15m/s.

        The spectrum is probably useless...

CONCLUSIONS :

  Follow-up

  * ASASSN-14ha      : BVRi

  * OGLE-2014-SN-073 : VRi

  * SN2014ad         : Gr13, bad seeing, probably useless

  Classifications

  * OGLE-2015-SN-060 : SN-Ia, z ~ 0.07

  * SNHiTS15I        : SN-Ia?, z ~ 0.15

  * SNHiTS15J        : SN-Ia?, z_gal = 0.11