sn2004dj %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% From: Alex Filippenko Date: Sun, 1 Aug 2004 11:00:26 -0700 (PDT) To: Kurt Weiler , Subject: bright supernova! Dear HST SN Ia team, There is a very bright (mag 11) SN in NGC 2403 (SN 2004dj); see below. We need to spectroscopically confirm it as soon as possible. It seems unlikely to be a SN Ia (it's in a cluster of bright stars), and if it *is* a SN Ia it's unlikely to be substantially before maximum brightness (it shows no evidence of brightening the past 2 nights). Moreover, it's in a very bad position in terms of supporting ground-based observations (extremely far east at the end of the night). Nevertheless, we should consider whether to trigger our HST program, if it turns out to be a very young SN Ia -- for such a bright, rare object, an "all-HST" campaign might be worthwhile. Please try to get observations as soon as possible and report them to me, as well as to Pete Challis (pchallis@cfa.harvard.edu). ALSO, regardless of whether you can get data for this object, please send your observing schedule for the next few months to Pete Challis, who will put it on our team web site (still being developed... hopefully will be available soon). Even if this object ends up not being a suitable SN Ia, it is so bright that we should try to get a good series of observations. Thanks. Alex Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION URL http://cfa-www.harvard.edu/iau/cbat.html SUPERNOVA 2004dj IN NGC 2403 S. Nakano, Sumoto, Japan, reports the discovery by K. Itagaki, Teppo-cho, Yamagata, Japan, of a bright supernova on at least ten CCD frames taken around July 31.76 UT using a 0.60-m f/7 reflector. The object is located at R.A. = 7h37m17s.02, Decl. = +65o35'57".8 (equinox 2000.0), which is roughly 160" east and 10" north of the nucleus of NGC 2403. The unfiltered (roughly V) mag was 11.2. Itagaki confirmed the object on Aug. 1.45, when it was estimated at mag 11.3. Nothing was visible at the object's location on Itagaki's numerous earlier CCD frames; specifically, it was not present to limiting mag 18.5 on 2002 Sept. 19 and Oct. 11. NOTE: These 'Central Bureau Electronic Telegrams' are intended to be preliminary announcements of items that later appear in the formal IAU Circulars. Citations should normally be made to IAUCs rather than to CBETs. 2004 August 1 (CBET 74) Brian G. Marsden %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% From: Alex Filippenko Date: Sun, 1 Aug 2004 11:40:43 -0700 (PDT) HST SN Ia team, For SN 2004dj ground-based observations at this time of the year, telescopes with alt-azimuth mounts are most useful... the object it difficult to reach with equatorial telescopes unless they are able to observe "under the pole." So... those of you with access to alt-az telescopes, your contributions would be especially important right now. Thanks. Alex %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% From: Alex Filippenko Date: Sun, 1 Aug 2004 13:57:30 -0700 (PDT) Subject: SN 2004dj HST SN Ia team, We are thinking of asking STScI whether we can use one of our TOOs to trigger on SN 2004dj, if it looks like a good object, regardless of whether it is a SN Ia. It would take only 7 orbits to observe at 7 epochs (one orbit every 2 days). The argument has been made that at V = 11 mag, the object will be quite bright in the UV unless the extinction is incredibly high. Moreover, though the object might be a relatively old SN II-P (the discovery was made on the first observation after a long time interval), there have not been good HST UV observations of such an object (SN 1987A was an unusual kind of SN II-P with a blue supergiant progenitor). Please let me know what you think of this possibility. To improve the process of making a decision, we need as much information as possible, as soon as possible. (We might try to tell STScI whether we will trigger on Tuesday of this week... in which case they could implement it into their schedule the week after that. The object nominally becomes observable with HST on August 4 [Sun-angle constraints, but this still has to be checked].) So... please supply a spectrum if possible (and note the strength of the interstellar Na D line, and the color). Please supply multi-filter photometry from which we could estimate a SN type, extinction, and age... and from which we could estimate the UV flux, at least crudely. Contact your friends at observatories! I realize we are near full Moon and the "wrong" kind of instrumentation is on many of the largest telescopes, but this object (V = 11 mag) can be observed easily with small telescopes. Report information to me, and to Pete Challis (pchallis@cfa.harvard.edu). Alex %%%%%%%%%%%%%%%%%% From: weidong li Date: Sun, 1 Aug 2004 14:03:44 -0700 (PDT) Cc: yamaoka@rc.kyushu-u.ac.jp Subject: Re: SN 2004dj If it is an oldish SN II-P, do we really need UV spectrum every other day, as it evolves rather slowly? Perhaps every 3-4 days to have a longer coverage is better? I realize that even SN II-P evolves relatively fast in the UV, but we still need to consider how often we have these HST UV spectra, especially if this is an old SN II. For a young SN regardless of its type, I agree that one spectrum every other day is a good strategy. Cheers, Weidong %%%%%%%%%%%%%%%%%% From: Alex Filippenko Date: Sun, 1 Aug 2004 14:11:37 -0700 (PDT) Cc: yamaoka@rc.kyushu-u.ac.jp Subject: Re: SN 2004dj Weidong, Of course, what you say is correct. That's one reason we would like to know as much about the SN as possible, BEFORE activating the HST program. But in the event that we *don't* know as much as we would like to, we have to activate the program in a way that will maximize the science for a youngish object.... HST TOO time is activated for at least a week at a time, because of the way scheduling is done. (In fact, I think STScI prefers that changes be made 2 weeks at a time, to decrease their level of stress.) We can't wait for the first HST spectrum, look at the UV, and then tell them to do something else 2 days later. So, Pete and I were simply working under the assumption that the object is young, to cover our best-possible case. But if new observations come in showing it is old, we will certainly modify our instructions to STScI... . but note that our instructions have to be sent to STScI either by this coming Tuesday or in 10 days (i.e., the Tuesday after that).... this is the way they operate, and we have to work within their constraints. Cheers, alex %%%%%%%%%%%%%%%%%%%%%%%% From: "Howie Marion" To: "Chris Smith" , "Alex Filippenko" We are observing SN 2004dj with the McDonald 2.7m using the coude cross-dispersed echelle spectrometer. We are also trying to obtain photometry with the 0.8m by looking between the trees. -Howie Marion and Carlos Allende Prieto %%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Date: Mon, 2 Aug 2004 19:34:49 +0300 (IDT) From: Eran Ofek Subject: SN2004dj - color and type Dear All, We measured the colors of 2004dj at Wise Obs. last night. here's a draft of a circular we are preparing. Eran Ofek, Dovi Poznanski, Dan Maoz, and Yiftah Lipkin (Tel-Aviv University) report: Based on BVRI observations of SN2004dj obtained on 2004-08-02 UT 02:00 with the Wise Observatory 1m telescope, we estimate the SN magnitudes and colors to be (corrected for Galactic extinction): V=11.67+/-0.04 R=11.19+/-0.05 B-V=0.50+/-0.08 R-I=0.34+/-0.11 Photometry was calibrated using a Tycho-catalog star in the field (see below for details). The attached plot shows the SN location in a color-color diagram (see Poznanski et al. 2002; http://wise-obs.tau.ac.il/~dovip/typing/). The SN colors are consistent with a type-IIn or type-IIP SN, several weeks past maximum, with reddening corresponding to about A_V=1 mag of extinction. Alternatively, the colors are also consistent with a pre-maximum type-Ia SN with about A_V=2 mag of extinction. The absolute magnitude is consistent with all these possibilities, assuming the Cepheid-based distance modulus to NGC 2403 of 27.5+/-0.24 by Freedman and Madore (1988, ApJ, 332, L63). However, a pre-maximum SN-Ia would be expected to be brightening more quickly. The measured position of the SN 07:37:17.12 +65:35:58.3 (J2000) [0.5"] is close (1") to a USNO-B1 source (R=17.56 I=16.76), and 0.6" from a 2MASS source (J=16.193+/-0.081 H=15.54+/-0.11 K=15.42+/-0.19). Improved astrometry/HST imaging is needed in order to see if this is the progenitor. Details of SN color amd magnitude calculation: ---------------------------------------------- We estimated the SN colors by measuring its colors relative to a nearby Tycho star (TYC 4120-1000-1; 07:37:10.11 +65:35:13.2) for which the magnitudes are known: B_T=10.58+/-0.04, V_T=9.97+/-0.03. We convert the Tycho magnitudes to Johnson magnitudes using the recipe in: http://www.projectpluto.com/photomet.htm giving for the star (B-V)_Johnson=0.52. Assuming the following NED-based Galactic extinction in the SN direction: A_B=0.20 A_V=0.15 A_R=0.12 A_I=0.09, the actual B-V of the star is 0.47, corresponding to an ~ F6 star. Given its measured proper motion, we can rule out the possibility that it is a supergiant. If a giant or a main sequence star it is at least ~100 pc away and therefore undergoes much of the disk's extinction along this line of sight. From Allen (2000), for F6 stars V-R=0.45 (MS) to 0.55 (giants) and V-I=0.74 (MS) to 0.94 (giants). Thus, the reference star has: B=10.43 V=9.91 R=9.41+/-0.05 I=9.0+/-0.10 Given the apparent magnitude of the star in the BVRI bands, we calculate the SN apparent mag: B=12.37+/-0.07 V=11.82+/-0.04 R=11.31+/-0.05 I=10.97+/-0.10 Correcting the SN color for Galactic extinction, the SN colors are: B-V=0.50+/-0.08 R-I=0.34+/-0.11 %%%%%%%%%%%%%%%%%%%%%%%%%%%%% From: Alex Filippenko Date: Mon, 2 Aug 2004 10:49:54 -0700 (PDT) Subject: SN 2004dj: to do, or not to do? Dear HST SN Ia team, You have all seen the results from the quick work of the Wise Observatory group (thanks!). The salient points are that the SN colors are consistent with a type-IIn or type-IIP SN, several weeks past maximum, with reddening corresponding to about A_V=1 mag of extinction. (The pre-max SN Ia alternative is highly unlikely because the object is not brightening quickly.) Should we try to trigger our program on this? STScI might not allow us to do so, since the science is really very different from what we had proposed... and if they do allow us, it might take them more than 1 day to decide, in which case we would not be able to trigger tomorrow (Tuesday) but rather a week from tomorrow. If we trigger today or tomorrow we can expect to get the observations on ~Monday August 9th. Because the target is very bright, and we don't have a "U" color, we may only be able to use the STIS/CCD with G230LB grating in the UV (i.e., down to about 1800 Ang). We could request a change to get the complete UV (down to 1200 Ang), but that observation would only take place about August 16 or so. Pete will work on the STIS ETC with the current colors and see if the safety checks can be met even for the first trigger. I looked into writing a DD (director's discretionary) proposal, but this would take time to write (minimum 1 day... a full proposal is required... and I will leave for a 1-week meeting in Vietnam in 3 days, so I am busy). It will also take time for STScI staff to evaluate, leading to a delay of at least a week (plausibly 2-3 weeks) before observations could be placed into the queue (with, of course, another few days to 1 week of delay before they are executed). Regardless of whether we try to trigger HST, we should follow this object from the ground, to the extent possible (it is very difficult or impossible to reach right now, with most telescopes... and it is completely inaccessible from the southern hemisphere. However, the questions for you right now are as follows: 1) Do you think we should try to trigger the *existing* HST program? 2) Do you think we should try submitting a DD proposal? My own opinion is that we should probably NOT trigger our HST program. I am willing to write a DD proposal, but only if you think the scientific gains are really great (given that the object will be at least a month old once HST gets to it). (If you vote for a DD proposal, I may write to you for a few sentences or paragraphs of scientific justification... Please send your replies to ME (*not* to everyone on the list... be considerate about flooding email boxes!) as soon as possible, but no later than 9 pm PDT tonight. Thanks. Alex %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% From: Alex Filippenko Date: Mon, 2 Aug 2004 22:44:28 -0700 (PDT) Subject: update on SN 2004dj (confirmed SN II-P), and strategies Dear HST SN Ia collaborators: Nando Patat reports that a quick look at a Calar Alto optical spectrum of SN 2004dj shows it to be "a Type II with a very well developed Halpha P-Cyg profile." Thus, it is a SN II-P, as suspected by the Wise Observatory team. There is overwhelming opposition to using SN 2004dj as our first trigger, assuming is is not a young SN Ia (which we now know is true). Many reasons were cited, including that it would "look bad" to the astronomical community and we would lose our credibility. Amazingly, however, today (Monday) the STScI staff *approved* a trigger on SN 2004dj, if we end up wanting to do so! Go figure.... Despite STScI's approval, it is my feeling (along with the majority of yours) that we should not trigger within our approved SN Ia program, so I won't. However, I am still exploring the possibility with STScI staff that this be approved as an *additional* TOO, possibly with additional DD orbits (though it would cost us < 10 orbits of time from our own program, which we could shave elsewhere if necessary, if the extra DD time were not approved). There are various arguments for spending at least a small amount of time on this supernova. I will keep you informed of developments. I'd like to address a few of Wolfgang's remarks: Yes, it is our intent to start with a Hubble-flow supernova, unless of course the next great very nearby SN Ia occurs first. It is NOT true that such events have occurred since the start of the program on July 1 -- we have been closely watching each candidate SN during the past month, and there simply has not been a suitable one. The LBL team (Greg Aldering, PI) will lead the analysis of the Hubble-flow supernovae (although everyone can contribute, in the spirit of this collaboration). Thus, there ARE people who "feel responsible" for them (indeed, the LBL team worked hard on the justification of this part of the proposal). Those SNe Ia will not fall between the cracks. The LBL "Nearby SN Factory" is gearing up to begin their first search of the season in the upcoming dark run. Moreover, my team's KAIT has been finding objects recently, with a cycle time of just 2 days between repeat observations... so we are likely to find a good one soon. I fully expect to activate the HST program in August, but we DO have to wait for a suitable candidate. KAIT has had two SN candidates in the past 2 nights, as I've reported to all of you in separate messages. We are awaiting spectral confirmation of them, or at least additional photometry. Based on the existing photometry, neither of these latest two candidates appears to be a young SN Ia. We will keep trying. Best wishes, Alex From: Alex Filippenko Date: Tue, 3 Aug 2004 01:11:01 -0700 (PDT) Subject: SN 2004dj optical spectrum coming in next message SN Ia HST collaboration: In the next message will be a postscript file showing the roughly calibrated Calar Alto spectrum of SN 2004dj, courtesy of Nando Patat and colleagues. Telluric absorption has not yet been removed, and there were some slit losses in the blue because the slit wasn't at the parallactic angle, but they cannot account for the flux plummeting in the U-band (it is due to line blanketing). The object is a normal SN II-P, a few weeks old (based on the well developed P-Cygni profiles, the low H-alpha absorption-line expansion velocity of about -5400 km/s, and the presence of strong Fe II and other low-ionization species). Interstellar Na I D is weak, but this may be a resolution effect. I will await the assessment of STScI staff regarding the likely prospects of a DD proposal, and the details of how it would be handled (e.g., would there be a long delay in getting data, could they just grant us another TOO, etc.). Opinions on how hard we should try for DD time, and with what urgency, would be appreciated (again, send these only to ME at this time). If you strongly want a DD proposal, please give me good reasons. Nino: I agree that this object should be studied in detail... but most of the science you gave (light echoes, VLBI, stellar environment, progenitor) could be addressed with a Cycle 14 proposal... in Cycle 13 the emphasis would be on UV spectra... so how strongly do we need these? Peter N: You mentioned you have lots of verbiage along these lines (the value of UV spectroscopy). Please send it to me. Note that, unfortunately, the existing HST images of NGC 2403 obtained for the Cepheid program do not include the site of SN 2004dj. Rats. Thank you, Nando, for your (and your colleagues') quick work. Alex %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Date: Tue, 03 Aug 2004 10:40:45 -0700 From: Stan Woosley Subject: Re: SN 2004dj optical spectrum coming in next message Reasons to study It may be the only chance in a long time to look at a SN II-p in the uv Other coordinated campaigns may be planned - e.g., see messages from Lewin re Chandra and INTEGRAL SN IIp are very interesting in there own right and - I suspect - have not been studied observationally in anything like the detail that Ia and even IBc have SN IIp can also be used for distance determination by the EPM. This might be a good test case. Stan Date: Tue, 03 Aug 2004 14:12:05 -0400 From: Nino Panagia Alex, I believe that there are good reasons to observe ANY BRIGHT SN in the UV, such as (1) To study the metallicity of individual SNe;\\ (2) To study the metallicity of the intervening ISM/IGM \\ (3) To study the kinematics of the {\it fast} moving (\ie the outermost layers) of the ejecta through the analysis of strong UV lines with P Cyg profiles\\ (4) To study the overall energetics of the SN explosion at early phases (from shock breakout to optical maximum for types of SNe, but most importantly for SNII).\\ (5) To study the strong emission lines produced in the interaction of the ejecta with pre-SN circumstellar material, \eg collisionally excited CIV 1550\AA, NIV] 1470\AA, OIII] 1665\AA, NIII] 1750\AA, CIII] 1909\AA, etc. I have drafted (see attachment) a Director Discretionary Time (DD) proposal that is a quick-and-dirty job done by cut-and-pasting paragraphs from my review on UV spectra of SNe and Cycle 11 SINS proposal. Although I am willing to work more on such proposal, I STRONGLY recommend YOU to be the PI because you have all technical tools that are needed to prepare, submit, and, later, to manage a successful proposal. Ciao - Nino filename="sn2004dj_dd_uv.txt" Supernovae create the chemical history of the Universe, energize the interstellar gas, form the spine of the extragalactic distance scale, and provide the only direct evidence for an accelerating universe. UV spectroscopy of supernovae is crucially important in order to:\\ (1) Study the metallicity of individual SNe;\\ (2) Study the metallicity of the intervening ISM/IGM \\ (3) Study the kinematics of the {\it fast} moving (\ie the outermost layers) of the ejecta through the analysis of strong UV lines with P Cyg profiles\\ (4) Study the overall energetics of the SN explosion at early phases (from shock breakout to optical maximum for types of SNe, but most importantly for SNII).\\ (5) Study the strong emission lines produced in the interaction of the ejecta with pre-SN circumstellar material, \eg collisionally excited CIV 1550\AA, NIV] 1470\AA, OIII] 1665\AA, NIII] 1750\AA, CIII] 1909\AA, etc. As summarized by Panagia (ref) the world's entire supply of good UV observations, (displayed in Figure 1 ?), is much smaller than we need to determine the bolometric behavior of supernovae, or to understand the circumstellar interactions of core­collapse supernovae, or to learn the restframe UV behavior of SN Ia so they can be used as cosmological probes at high redshift. HST is the only way to observe these UV spectra. SN 1999em II STIS (9d) SN 1998S IIn STIS (12 days after explosion) SN 1992A Ia FOS (11d) SN 1993J IIb FOS (10d) Figure 1: SINS First Epoch HST UV Spectra Despite the fact that Type II plateau (SNIIP) supernovae account for a large fraction of all SNII, so far SN~1999em in NGC 1637 is the only SNIIP that has ever been studied in some detail in the ultraviolet (see Table 1). Although caught at an early stage, SN 1999em was quite past maximum light (\eg~ \cite{hametal01-NP}), which may account for the fact that its spectrum on 1999 November 5 (see Fig.12) is not as blue as that of SN~1998S on 1998 March 16, when the latter was just around maximum light. A preliminary analysis of the optical and UV spectra made by Baron \etal~ (\cite{betal00-NP}) using the SYNOW synthetic spectrum code that spectroscopically this supernova appears to be a normal Type II, and the models are in excellent agreement with the observed spectra. Also in this case the analysis suggests the presence of enhanced nitrogen as found in other SNII. More refined analysis of these spectra done with the full non-LTE general model atmosphere code PHOENIX (\cite{betal96-NP}) is not able to confirm or disprove a N enhancement but conclusively requires enhanced helium. Another important result is that very early spectra such as those obtained for SN~1999em combined with sophisticated spectral modeling can lead to an independent estimate of the total reddening to the supernova, since when the spectrum is very blue, dereddening leads to changes in the blue flux that cannot be reproduced by altering the ``temperature'' of the emitted radiation. These results are extremely encouraging since they imply that detailed modeling of early spectra can shed light on both the abundances and total extinction of SNe II, the latter improving their utility and reliability as distance indicators. Here we propose to make STIS observation of SNII-P 2004dj in the nearby spiral galaxy NGC 2403 (D~3.4+/-0.4 Mpc; Freedman and Madore 1988), recently discovered (IAUC 8377), and promptly classified as a SNIIP (Patat et al, IAUC tbd) and detected at high radio frequencies with the VLA (Weiler et al, IAUC tbd). Because of its proximity to us, the SN is quite bright (V~11.2) and its light is attenuated by a quite modest extinction (E(B-V)<0.3; Ofek et al IAUC? tbd?)). We will follow the same observational scheme as developed by the SINS project because it proved very effective in covering the SN event quite accurately, while requiring just a minimum of observing time. Such a strategy has been tested successfully with SN 1992A (SN Ia), SN 1993J (SN IIb), SN 1994I (SN Ic), SN 1998S (SN IIn), and SN 1999em (SN II) to gather unique spectra in the UV with HST. In particular, we plan to observe at the earliest moment the HST system will allow, a week later, at age 2 weeks, and at an age of about 50 days. Effective target acquisition schemes have been worked out in detail during Phase 2 for earlier cycles. Lo dispersion UV spectra give the overall energy distribution, which has proved dramatically different for various types of supernovae and is a sensitive indicator of the physical state of the outermost layers of the explosion and the circumstellar surround. ACS/HRC imaging (NUV?, optical?) provides the most unambiguous vision of the SN and its environment, which are essential to characterize correctly its nature and properties. We need 3 orbits for the first visit (1.7 orbits with G140L, 1.0 orbits with G230L, and 0.3 orbits with the G430L), 5 orbits for the second visit [G140L (3 orbits), G230L (1.7 orbits), and G430L (0.3 orbits)], 5 orbits for each of the two later measurements, and 1 orbit for the ASC/HRC imaging, a total of 19 orbits for the ToO. From: Alex Filippenko Date: Tue, 3 Aug 2004 11:18:09 -0700 (PDT) Subject: Re: SN 2004dj optical spectrum coming in next message Nino, Thanks for your note. I have already submitted (very recently) a proposal to the acting director, Bob Williams, for DD time on HST. I submitted it on behalf of the collaboration, explaining that we don't want to trigger one of our SN Ia TOOs. I will see whether I can incorporate some of your verbiage into a revised draft of my proposal. Next time you undertake something pretty major like this, please tell me! I've been working much of the night, and discussing things with STScI staff all morning, so it would have been helpful to know what you're up to. But I very much appreciate the work and will try to incorporate it. best, alex From: Alex Filippenko Date: Tue, 3 Aug 2004 15:37:33 -0700 (PDT) Subject: a roller-coaster day for SN 2004dj project HST team: Brief summary, as I am late for something. Good news: STScI approved my DD request! The deal is that we are NOT charged a TOO (so we still have 7 for SNe Ia). We *are* charged for the orbits, but there are only about 7 of them, so we just shave an average of 1 orbit from the 7 SNe Ia -- can do, especially for the brighter ones. We also got (at my request) 2 orbits of WFC/ACS imaging of the galaxy and SN for free, as a PR picture -- a great photo showing a beautiful spiral galaxy with a bright supernova. B,V,I images, probably in 2 fields to cover the entire galaxy. Bad news (potentially very bad): STIS operations are currently suspended, and might remain that way forever if the problem is not fixed. It has something to do with the voltage, and to me smells a bit like the failure a few years ago of the first power unit. If this backup fails as well, STIS might (will?) be dead. I don't know much more at this time. The first STIS observations of SN 2004dj (if STIS is operational) will occur no earlier than Aug 16, due to other programs being executed. The plan is to get UV spectra (spanning through the optical at essentially no cost in time) at something like 5 phases, being sure to cover the transition from the plateau to the steep decline to the nebular phase. More later. Keep your collective fingers crossed for STIS, or most of our proposed and approved science for SNe Ia (and 04dj) will not be doable. This would be a huge blow. Alex From: Alex Filippenko Date: Tue, 3 Aug 2004 16:41:42 -0700 (PDT) Subject: STIS "suspend" update HST SN team, Here is the latest on STIS, from STScI. Meanwhile, please continue to observe SN 2004dj if you can, at all wavelengths. Also, try to get spectral confirmation of the recent KAIT SN candidates. Thanks. Alex %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% te: Wed, 15 Sep 2004 13:54:54 +0900 From: "Koji S. Kawabata" Subject: QL of Subaru 2003jd spectroscopy To: Elena Pian Cc: Paolo Mazzali , Ken Nomoto , Jinsong Deng , Keichi Maeda , Lifan Wang , jeffery@kestrel.nmt.edu, tmatheson@cfa.harvard.edu Dear Elena and colleagues, We successfully observed some SNe with Subaru on Sep 10 and 11 HST. Here is the spectrum of SN 2003jd. It is highly contaminated by underlying gal. and its H II region. In the resolution of our image, the point-like H II region is completely superimposed on the SN. The broad [OI]6300,6363 lines seem to have double-peak. The MgI]4572? also seems double-peaked. If it is real, we could suggest the difference of viewing angle for the asymmeric outburst between 1998bw and 2003jd (cf. Maeda et al. 2002). Follow-up spectroscopy is recommended. Now I must leave office and I will report on other SNe later. Koji From: "Jinsong Deng" To: "Koji S. Kawabata" , Subject: Re: QL of Subaru 2003jd spectroscopy Date: Wed, 15 Sep 2004 14:57:36 +0900 How does this compare with the multi-peak profiles in late 93J spectra? jinsong Date: Wed, 15 Sep 2004 14:38:53 +0200 (CEST) From: Paolo Mazzali To: "Koji S. Kawabata" Cc: Elena Pian , Ken Nomoto , Jinsong Deng , Keichi Maeda , Lifan Wang , jeffery@kestrel.nmt.edu, tmatheson@cfa.harvard.edu Subject: Re: QL of Subaru 2003jd spectroscopy Dear All, this is a really exciting result! As you know, I have been saying for years that if these "weak hypernovae" are off-axix things the best evidence would come from double peaked [OI]. This is now what 03jd is showing. With a simple model (Keichi, you probably have some in your library) we may use just this spectrum for a letter, possibly even to Nature given the current debate. Let us discuss people's opinions here. Cheers Paolo From: "Jinsong Deng" To: "Paolo Mazzali" , Paolo: Is this your picture? O and Mg is concentrated along the equator direction. Our line of sight is close to that direction. And there is not much material in the innermost core of the ejecta, in contrast to 98bw. Do we need to confirm what we see in the spectrum are double peaks, not multiple ones superimposed upon a box? Koji: Is its brightness enough for a HDS observation? We have one HDS night on Sep30. jinsong Date: Wed, 15 Sep 2004 15:58:55 +0200 (CEST) From: Paolo Mazzali Subject: Re: QL of Subaru 2003jd spectroscopy Hi Jinsong, > Paolo: Is this your picture? > > O and Mg is concentrated along the equator direction. > Our line of sight is close to that direction. And there is not much > material in the innermost core of the ejecta, in contrast to 98bw. > exactly. a study of the LC should confirm the absence of low-velocity stuff. > Do we need to confirm what we see in the spectrum are > double peaks, not multiple ones superimposed upon a box? > the figure looks very clear. How could those peaks be a coincidence? Koji, have you any idea? > Koji: Is its brightness enough for a HDS observation? > We have one HDS night on Sep30. > cheers Paolo %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%5