[Message Prev][Message Next][Thread Prev][Thread Next][Message Index][Thread Index]

[vsnet-history 1159] SN 1993J (Wijers)




Date: Wed, 23 Jun 93 10:11:06 EDT
From: Ralph A.M.J. Wijers <rw@ourania.Princeton.EDU>
Subject: version 9 of 1993J conflicts list

##
## $Author: rw $
## $Date: 1993/05/17 14:21:10 $
## $Locker: rw $
## $Revision: 1.3 $
## $Source: /amd_tmp/astro/export/home/rw/supernova/RCS/1993j.conflict,v $
## 
      ################################################
      #   conflicts of 1993j.mag with other lists    #
      #   and other unresolved issues with SN1993J   #
      #   magnitude estimates                        #
      #   Version 9   23 June  1993                  #
      ################################################

Here are the conflicts between compilations/reports that I found.
Anyone able to shed light on them is kindly asked to let the 
communicity know about it.

general:  
========

ALERT: the star reported to be variable by Hanzl (IAUC 5776) is indeed
used in many estimates, e.g. by the Spanish and Norwegian groups. It is 
the 10.7 mag star NW of the galaxy, doubly underlined in the Thomson-Bryan chart.
According to gav's report, it is star D in the AAVSO and BAA/The Astronomer
alert charts.
DO NOT use it anymore. If you have past measurements which are based
on this star, please report them. If you had enough stars, revise the
magnitude, if not, preserve the raw data you have. Perhaps the variations
will turn out to be periodic, so we can reconstruct the brightness at any
given time and revise the magnitudes from the raw data.

ALERT: according to De Veaucouleurs, the 14th mag star close to the 
       supernova is also variable, as reported by Brian skiff of Lowell Obs.
update 19930618: It turns out that it is constant after all (see note by gav)

Appleton etal. photometry: Appleton informs me that they use Johnson/Harris
       BV filters, and almost pure Johnson RI. Their photometry is relative
       to corwin's standards and without colour corrections.
      
Bjorn Granslo's list: many cases where I noted TB as reference from regular
            updates sent on behalf of the Norwegian Variable Star
            observers have TA as reference in his compilation. Why?

LaPalma photometry: the results presented in a recent ESO messenger from the
       photometry done at La Palma are included with values rounded to
       2 decimal places (given are 3). Errors are uniformly set 0.01 mag,
       but are often less in reality.
		      
Spain: the discovery group, Garcia, Pujol, Ripero: 
       If I plot their measurements for comparison with all the others, it 
       seems that from 04/01 to 04/06, they are in line with the rest,
       from 04/06 to 04/12, they are significantly fainter, and from 04/12 on
       they are significantly brighter. I did not yet make such plots for
       all other observers, but from what I saw sofar, theirs seem strange.  
       Since their early points are almost the only early ones we have,
       I feel we should make some effort to sort this out.
       It should be noted that Rodriguez's CCD measurements are off in
       exactly the same sense as the visual estimates of the group.
       This makes me suspect that at least part of the deviation could be a 
       matter of comparison stars.

       Update 19930426: I got a message from
       Bjorn Granslo, who received a fax from Ripero, listing
       all Spanish measurement on or before March 31. This clears up
       a lot of confusion. The measurements that are now in my list
       are the only correct ones, all other times/magnitudes should
       discarded.

       Update 19930506: we now have the raw estimates for the early 
       Spanish measurements, and apart from some of them using the possibly 
       variable star D (mv = 107 on TB chart), they are OK. 
       Nothing new on the later ones.

       Update 19930617: the Spanish measurements near the first minimum and
       second maximum are still significantly off the rest, but we have their
       raw data, so that's what it will remain. Their later data are again in
       line with other people's estimates.

specific entries:
=================
Note: all items containing a "resolution(Date)" will be gone in the next
      version.

04 01.083 Schmeer      Germany 10.7  0  TB  SELF \ In the email I got from 
04 01.083 Schmeer      Germany 10.7  0  AC  kat / he quotes the "Supernova
     Search Chart" = TB for all his measurements. The sequence listed by
     Kato/Granslo for his data varies from point to point. I think we
     have to quote TB for all of them.

               followup (19930506): TB accepted for this measurement. Some later
				    data by Schmeer are quoted as TA, perhaps
				    he could clarify the issue himself?
	       resolution (19930618): TB accepted for all measurements 
				    because that's what Schmeer reports.

04 05.15  Levy     12.1 mv TB  SELF 04/XX  \  Levy accepted, because he correc-
04 05.15  Levy     11.6 mv     gmh 04/14  /  ted his 11.6 estimate personally.
               followup (19930506): Granslo and Kato lists still give 11.6. To
				    convince everyone of the correctness of 12.1,
				    here is a piece of his email to me:
>> I'd earlier posted an estimate on April 5.15 of ".2 mag fainter than B"; I
>> was calling star B mag 11.4, which seems to be its GSC tabulated V brightness,
>> and so called SN1993J mv 11.6.  Michael's recent note calls B mv 11.9 not 11.4
>> (quoted from T&B); I'd like to revise my estimate accordingly.  So:
>> 
>> Date       SN1993J mv    System
>> April  5.15     12.1        "TB & Richmond"
>> April 10.14     11.2        "TB & Richmond"
>> 
>> Stuart Levy, Geometry Center, University of Minnesota

               followup (19930517): Granslo and Kato lists still give 11.6.
	       resolution (930618): everyone now lists 12.1


04 06.140 Beauchamp 11.7 mv TB SELF        \  self given precedence
04 06.099 Beauchamp 11.7 mv TB grl 04/18  /
               followup (19930506): Kato now lists both, Granslo lists 06.140.
				    I kept both as well, but I re-checked my
				    mail, and only have Beachamp's report for
				    06.140. I will therefore remove 06.099
				    in version 6, unless Beauchamp says otherwise.
               followup (19930517): Situation unchanged. I deferred deleting 
				    the 6.099 data, until I get a reply from 
				    Beauchamp about the matter.
	       followup (19930518): Beauchamp replied as below, so I removed 
				    the 6.099.
>>		From beaucham@phy.ulaval.ca Mon May 17 22:12:18 1993
>>		Subject: Re:  Your measurements
>>		Hi Ralph,
>>		I checked my logbook.  I found only a line for April 6.140 UT,
>>		Mv=11.7.  So, the entry for April 6.099 is not mine.  Remove it!
>>		Dominique

	       followup (19930618): Granslo has removed 6.099, Kato still lists
	                            it

04 13.2   Shaeffer, R.     grl 06/14 \   I check his name on his email, and
04 13.2   Sheaffer         rw  06/18 /   Sheaffer is correct. Same goes for
					 all other entries by the same observer
					 in grl's list. Some entries in kato's
					 list have same mistake

29/04/93  0.890 12.0         A Eklof                 (gmh 05/31)
1993 04 28.89   12.0  mv     Ekloef, A.  Mail(ben)   (grl 06/14)
1993 04 29.890  12.0  mv    *Eklof, A.   Mail(gmh)   (grl 06/14)
	  The name Ekloef is not found in GMH, and Eklof not in GRL except for
	  this case, quoted as "Mail(gmh)". Since all other cases of Eklof
	  in GMH have an exact match to an Ekloef in GRL, I suspect that these
	  are the same person, and that the Eklof 04/29.890 may well be a copy
	  error. Could Bjorn, who apparently has the orginal report by 
	  Bengtsson, verify/falsify this? Meanwhile, I will assume that the
	  04/29.89 entry should be deleted.

01/05/93  0.957  12.3    M Westlund      TA  (gmh 05/31) \  grl given priority
1993 05 01.928  12.3  mv TA  Westlund, M.    (grl 06/14) /

1993 05 09.893  12.5  mv TA+ Dahle, H. \ granslo's version 11
1993 05 09.892  12.5  mv TA+ Dahle, H. | granslo's summary of Norwegian results
					 of 05/10 and Hurst's report of 05/31
					 9.892 given priority.


Return to Home Page

Return to the Daisaku Nogami

vsnet-adm@kusastro.kyoto-u.ac.jp

Powered by ooruri technology