From: Tony Spadafora (ALSpadafora@lbl.gov)
Date: Mon Jul 03 2006 - 13:14:36 PDT
HI all,
Proposed dates for a teleconference are:
Tues Jul 11
Wed Jul 12
Tues Jul 18
Wed Jul 19
Proposed start time is 10:00 PDT. With updates on progress from the
cluster groups and discussion of new ideas, we might plan on 1.5-2
hrs. Please let me know if you are available at these times (and if
not, please suggest alternative times - preferably during the weeks
of July 10 or July 17).
Regards,
-Tony
On Jun 28, 2006, at 6:17 PM, Saul Perlmutter wrote:
> ...One extra note to add to the status report: Tony will be
> trying to set up a conference call in the next few weeks for
> discussion of plans, so watch for email from ALSpadafora@lbl.gov
>
> --Saul
>
>
> Kyle S Dawson wrote:
>
>> Hi All,
>>
>> I also feel that I have not done a good job updating everyone with
>> the
>> status of the SN search, so let me take this oppurtunity to do
>> so. I'll
>> start with a simple laundry list of what we've found, and then
>> summarize
>> our initial interpretations and some issues yet unresolved.
>> There are now 25 clusters in the program. Three of these were
>> added in
>> Dec-Apr using free orbits from supernova-less clusters. All three of
>> these new clusters come from archival XMM data. Observations are
>> complete for 19 clusters. If I remember correctly, the search for
>> SNe
>> in 5 of the remaining 6 clusters will end in late July, and the last
>> cluster search will end in late Aug. Those dates need to be
>> double checked.
>>
>> The full cluster list, images of SNe, etc can be found on the TWiki:
>> http://hstclustersn.lbl.gov:8081/twiki/bin/view/Supernovae/WebHome
>> usrname: TWikiGuest
>> passwd: hstclustersn
>>
>> Current status:
>>
>> Orbits used: 158 ACS, 21 NICMOS
>> Remaining UNscheduled orbits: 7 ACS, 9 NICMOS
>>
>> ***BEGIN LAUNDRY LIST*******
>>
>> SNe discovered:
>>
>> Active:
>> A-004: Awaiting spectroscopy using Subaru and VLT this week.
>> Host is
>> red, possible early type, but SN is too bright to be associated with
>> z=1.4 cluster. SN color/mag, consistent with z~1.0-1.2.
>>
>> Cluster E hosts:
>> O-000: z=1.01
>> K-000: z=1.41???Waiting better spectroscopy, hopefully tonight
>> H-005: z=1.23
>>
>> Other cluster SNe
>> C-001: z=0.98, spectroscopically confirmed Ia, host faint and
>> uncertain
>>
>> SNe hosted by E type galaxies with no emission lines in background of
>> clusters:
>> O-006: z=1.31
>> C-000: z=1.09
>> G-004: z=1.35
>>
>> low z field SNe (probably not useful for cosmology, maybe for rates)
>> N-010: z=0.203, type unknown
>> P-001: z=0.92, type unknown
>> P-009: z=0.821, Ia
>> X-027: z=0.4, type unknown (probably core collapse)
>> C-007: host uncertain, type unknown
>> G-003: z=0.963, type unknown
>> F-008: host uncertain, type unknown
>> H-003: z=0.851, Ia
>> Z-005: z=0.624, Ia
>>
>> possible z>1.5 SNe (based on SNe color/mag, host color/mag):
>> X-018: one epoch, faint red host
>> X-026: two epochs, faint red host
>> T-001: one epoch, faint red host
>>
>> undetermined redshift, discovered this week in reverse subtractions
>> (last epoch as ref, first epoch as search). Three have faint
>> hosts that
>> appear spiral or irregular, with SNe and host consistent with
>> z>1. We
>> hope to find emission lines in spectroscopic observations next
>> spring.
>> E-012: faint host
>> F-012: faint host, SNe color, lightcurve consistent with z>1 Ia
>> K-018: possible cluster E, z=1.41, SN probably not useful for
>> cosmology
>> due to poorly sampled lightcurve, very good for rates,
>> spectroscopy of
>> host tonight, weather permitting
>> L-021: faint host
>>
>> And finally, one mystery object:
>> F-006: galactic, extragalactic, z=0.54, quasar, SNIc, hypernova, pop
>> III SN, star??????? Nothing in the lightcurve or spectrum resembles
>> anything this group has seen before. The transient is hostless to a
>> limiting mag z'>26.5, i'>26.5. At max, the transient has z'=21.2 and
>> i'=21.1.
>> The lightcurve has a risetime of 100 days with no evolution in
>> color. The spectrum has features semi-consistent with a SNIc at
>> z=0.54, but
>> lacks key Fe features. We posted an IAUC, or CBET as they are now
>> called, and have an article written about it here:
>> http://www.newscientistspace.com/article/dn9360-enigmatic-object-
>> baffles-supernova-team.html
>> We got more data on this in poor conditions Sunday night at Keck and
>> last night at Subaru, there is clear continuum but the spectra are
>> still
>> waiting to be reduced.
>>
>> Unresolved issues: several SNe hosts have not been observed. We got
>> murdered with Mauna Kea weather this spring and lost almost all of
>> our
>> time. We will try to pick up these redshifts in spring 2007.
>>
>> *******END LAUNDRY LIST************
>>
>> Now, as it stands we do have unscheduled orbits. If these orbits are
>> still free in Aug, we plan to return to the 5 RCS clusters in the
>> 02-04
>> hr range for a second round of searching. We will have deep
>> references
>> from the 2005 data for the search, and have Keck DEIMOS time
>> scheduled
>> to coincide with these HST visits. We will use 5-10 orbits,
>> depending
>> on how many are free. If a SN is found, we will follow the
>> lightcurve
>> using the remaining unscheduled orbits. If no SN is found, we will
>> preserve those last orbits to use as ToO for a SN search using time
>> awarded to PRME et al in cycle 15 for observations of a new set of
>> IRAC
>> clusters.
>>
>> One thing that is very interesting to note is that we have a
>> fairly high
>> rate of SNe with z>1 E hosts, but a low rate of late type hosts at
>> this
>> redshift. This is very surprising and we do not have an answer
>> for the
>> low rate of late type hosts. In terms of cosmology, the z>1 E hosts
>> should be extremely useful. The SN are often un-typed, but we
>> plan to
>> obtain deep spectroscopy of the hosts in order to place
>> constraints on
>> star forming and argue for Ia SNe. We believe these SNe should be
>> dust-free as well, but this clearly needs to be explored. These
>> SNe are
>> also in the background of massive clusters, and are therefore
>> subject to
>> magnification via lensing. In order to use these for cosmology,
>> we will
>> need to remove this bias using estimates of cluster masses. We
>> have two
>> students working on this, and I'd like them to explore different
>> techniques of measuring cluster mass. We may be asking for some help
>> with that. For the purposes of cosmology, a 2\sigma measurement
>> of mass
>> through weak lensing is probably fine, but it will be very good
>> for the
>> two students to learn the other methods as well.
>>
>> And finally, we plan to perform a rates analysis. This is the
>> best data
>> set of high z cluster SNe, and the measurement of rates in the
>> cluster
>> environment should be a very good result. To do so, we will need to
>> come to some consensus on how to define the cluster environment. The
>> cluster sample is clearly inhomogeneous so this may require a bit of
>> work. Something to think about for this telecon Marc Postman
>> suggests.
>>
>> -Kyle
>>
>>
>> ----- Original Message -----
>> From: Marc Postman <postman@stsci.edu>
>> Date: Wednesday, June 28, 2006 9:13 am
>> Subject: Cluster science status
>>
>>
>>> Saul, Mike, et al.,
>>>
>>> I am wondering if others feel as out of the loop as I on what's
>>> happening with the cluster science part of the program and who
>>> is doing what now. If I am not alone in this, it might be time
>>> for a telecon to at least get an update on progress and
>>> discussion of possible new ideas to pursue with the data.
>>>
>>> -Marc
>>>
>>> -----------------------------------------------------------------
>>> Marc Postman Email: postman@stsci.edu
>>> STScI - CMO Phone: +1-410-338-4340
>>> 3700 San Martin Drive Fax: +1-410-338-4796
>>> Baltimore, MD 21218 U.S.A. http://www.stsci.edu/~postman
>>>
>>>
>>>
>>>
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