Status of spectroscopy reduction from low-z working group @feb 2001

The low-z working group started working at the data in June 2000. Here is a report of the working progress until November 2000.

The aim of this document is to summarize the situation of the spectroscopic data, the status of the reduction, and give comments and information about the ongoings.

All the information and the links you find in this page are also somewhere in the Collaboration Section of the snova web page: www.physto.se/~snova


Remember the low-z set of data?!

SET of DATA

WHO WHAT HOW MANY NIGHTS SNe
Stockholm
NOT
INT
KPNO4.0
Lick3.0
ESO3.6
6
2
2
4
6
sn99bk,sn99bp,sn99bm,sn99bq,sn99aa,sn99ak,sn99au,sn99as,sn99aw,sn99ac,sn99z,sn99ab,sn99ae,sn99ai
sn99aa,sn99bh
sn99bk,sn99bp,sn99bn,sn99au,sn99as,sn99aw,sn99ac,sn99bh,sn99ax,sn99ay
sn99bp,sn99be,sn99aa,sn99as,sn99aw,sn99ac,sn99bh,sn99ai,sn99ah,sn99ax
sn99bq, sn99ac, sn99ao, sn99bi, sn99av, sn99bm
Berkeley
APO3.5
CTIO4.0
Ref@Lick3.0
Ref@CTIO4.0
Ref@KPNO4
6
4
3
4
3



Here is a table containing useful information about the reduced SNe (type, date of max, how many spectra we have for each supernova, S/N ratio). Note that the signal to noise ratio needs to be updated, because the background was not considered at the time the table was builded up. We hope we will be able to give the corrected values very soon. A more useful database is currently under development(Nicolas will speak about )


Our reduction scheme can be seen in our web page. It has been updated several times since last June, thanks also to the careful reading of Alex Conley. The most important update is about the background subtraction, and the way we consider it in the final error.



A report about the way we compute statistical and systematic errors is available also in our web page. (In the same page you can find other documents we wrote)
The IDL programs that have been written to compute the errors will be soon available on our web page. Contact Serena if you want to know more.



The status of reduction in Stockholm is the following:
  • We reduced all the spectroscopic nights at NOT, KPNO4.0, Lick3.0

  • We extracted the INT spectra, but we couldn't calibrate them in wavelength. It's not a big deal since there are only 3 spectra of 2 SNe, but it would be nice to have them done also.

  • Ongoing reduction of ESO3.6 spectroscopic data: done 2 out of 6 nights

  • Ongoing correction of the computed sigma for the whole set of data, to take into account the subtracted background.

  • Some of the Lick data (red channel) have fringing. We are trying to figure out how important it is to correct it, and how to do it.

  • We have never edited cosmic rays. They usually give us no problems, and the combination of more spectra can generally get rid of them when they are on the spectrum. In the cases this doesn't happen we are going back to the 2D image and delete them.


The status of reduction in Berkeley is the following:
  • Almost completely reduced the 4 nights at CTIO4.0. Susana is taking care of them.

  • References to be reduced completely. Alex is in charge of them.

  • APO3.5: nothing has been done on this set of data until now.





For comments, suggestions or questions about this page to can contact serena@physto.se
e-mail distribution list to reach all current members of the team: nearsearch99@physto.se.
Last modified:Mon Feb 12 13:30 MET 2001