%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2107 SUBJECT: GRB 030329: Supernova Spectrum Emerging DATE: 03/04/07 01:54:45 GMT FROM: Krzysztof Z. Stanek at CfA T. Matheson (CfA), P. Garnavich (Notre Dame), N. Hathi, R. Jansen, R. Windhorst, L. Echevarria (ASU), J. Lee (Arizona), W. Brown, N. Caldwell, P. Berlind. M. Calkins and K. Z. Stanek (CfA) report: We obtained spectra of the afterglow of GRB 030329 (Peterson & Price, GCN 1985; Torii: GCN 1986) with the 6.5-m MMT and Blue-Channel spectrograph each night from March 30.12 to April 6.15 (UT). The spectra cover a wavelength range of 350 nm to 850 nm with a resolution of 0.6 nm (FWHM). The early spectra consist of a power-law continuum with narrow emission lines originating from HII regions in the host galaxy (Martini et al. GCN 2013; Della Ceca et al. GCN 2015; Greiner et al. GCN 2020; Caldwell et al. GCN 2053). However, our spectrum taken Apr. 6.15 (UT) shows a broad peak in flux at approximately 570 nm and another weak deviation from a power-law near 470nm that were not evident in the earlier spectra. The April 6 spectrum is well reproduced by adding a spectrum of SN 1998bw (Patat et al. 2001, ApJ, 555, 900) seven days before maximum light to a power-law distribution. We conclude that a supernova spectrum is emerging from the afterglow light. The brightness of the supernova is approximately V=22 based on the strengths of the broad features relative to a pure power-law. Further spectroscopy is planned. A plot of the spectrum compared with SN 1998bw is available at: http://cfa-www.harvard.edu/~tmatheson/grb030329_sn.jpg This message may be cited. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2117 SUBJECT: GRB030329: HET spectroscopic monitoring DATE: 03/04/08 03:37:04 GMT FROM: Mike Eracleous at PSU, Astro.Dept. Mike Eracleous (Penn State), Brad Schaefer, and Chris Gerardy (U. Texas) on behalf of the Hobby-Eberly Telescope GRB followup team report: We have obtained several spectra (410-900 nm, resolution 1.6 nm) of the optical counterpart of GRB030329 (Peterson & Price, GCN 1985; Torii: GCN 1986) with the Hobby-Eberly Telescope and Marcario Low-Resolution spectrograph. Our spectra of March 31, April 2, and April 5 (UT) show the following evolution of the spectral properties: (a) the equivalent widths of the [O III] and H-alpha emission lines is increasing in a manner consistent with a constant line flux and a decline of the continuum, and (b) the spectrum of April 5 (UT) shows evidence of a broad feature underlying the [O III] lines, similar tresembling that reported by Matheson et al. (GCN 2107), who interpret it as due to an emerging SN spectrum. However, the contrast of this feature in our spectrum is not as high as in the spectrum of Matheson et al. (taken a day later than ours). As a consequence, we cannot rule out alternative interpretations, such as the emergence of a host galaxy spectrum that manifests itself as a break in the power-law continuum. Analysis of more recent spectra is under way to clarify this issue. Using the [O II] and H-alpha emission line fluxes of Caldwell et al. (GCN 2053), we estimate luminosities of 1x10^40 and 4x10^40 erg/s, respectively (for z=0.168, i.e., a luminosity distance of 880 Mpc), and infer star formation rates of 0.15 and 0.32 solar masses/yr (following Kennicutt 1998, ARAA, 36, 189). The upper limit on the host galaxy from historical images reported by Wood-Vasey et al. (GCN 1998; R > 22.28) implies a limit on the absolute magnitude of M_R > -17.4, which is comparable to that of the LMC. The [OIII]/H-beta ratio of 2.7 (Caldwell et al.; GCN 2053) corresponds to an LMC-like faint starburst galaxy (Ho, et al. 1997, ApJ, 487, 579, Figure 6; Hunter & Gallagher, 1997, ApJ, 475, 65; Hunter et al. 2001 ApJ, 553, 121), while the H-alpha luminosity is characteristic of starburst galaxies (Ho. et al. Figure 2). High-dispersion spectroscopy of these narrow lines may give more information on the nature of star formation in the host galaxy. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2120 SUBJECT: GRB 030329: Supernova Confirmed DATE: 03/04/08 20:13:40 GMT FROM: Krzysztof Z. Stanek at CfA T. Matheson (CfA), P. Garnavich (Notre Dame), E. W. Olszewski (Steward), P. Harding (Case Western), D. Eisenstein (Arizona), B. Pindor (Princeton), N. Hathi, R. Jansen, R. Windhorst, L. Echevarria (ASU), J. Lee (Arizona), W. Brown, N. Caldwell, P. Berlind, M. Calkins and K. Z. Stanek (CfA) report: Additional spectra of the afterglow of GRB 030329 (Peterson & Price, GCN 1985; Torii: GCN 1986) were obtained with the 6.5-m MMT on Apr. 8.13 UT. The spectral features discovered by Matheson et al. (GCN 2107) and confirmed by Garnavich et al. (IUAC 8108) continue to develop. Subtracting a scaled version of the Apr. 4.27 UT power-law spectrum from the Apr. 8.13 spectrum reveals an energy distribution remarkably similar to that of the SN1998bw a week before maximum light (Patat et al. 2001, ApJ, 555, 900). This spectrum can be seen at http://cfa-www.harvard.edu/~tmatheson/compgrb.jpg The spectral similarity to SN 1998bw and other 'hypernovae' such as 1997ef (Iwamoto et al. 2000, ApJ, 534, 660) provides strong evidence that classical GRBs originate from core-collapse supernovae. This message may be cited. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2121 SUBJECT: If the SN/GRB connection confirmed DATE: 03/04/09 05:33:01 GMT FROM: Vladimir Sokolov at SAO RAS V. Sokolov (SAO RAS) reports: Congratulations to all "GRB-fans"! At last! I will permit myself to make a short comment to GCN#2120 (T. Matheson et al.). If all "...classical GRBs originate from core-collapse supernovae", as was mentioned in the GCN #2120, it would inevitably have consequences for both a collimation angle, and the GRBs energy (see details in astro-ph/ 0102492 or astro-ph/0107399), and all the GRB scenarios. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2131 SUBJECT: GRB 030329 and SN 2003dh DATE: 03/04/10 04:56:26 GMT FROM: Ryan Chornock at UC Berkeley R. Chornock, R. J. Foley, A. V. Filippenko, M. Papenkova, and D. Weisz, University of California, Berkeley, report that inspection of CCD spectra (range 310-1000 nm) of GRB 030329, obtained on Apr. 8 UT with the Shane 3-m telescope at Lick Observatory, confirms the emergence of broad bumps (especially at rest-frame 500 nm) characteristic of the peculiar type-Ic supernovae 1998bw and 2002ap at early times, as announced by Matheson et al. in GCN 2107 and GCN 2120. The association between core-collapse supernovae and at least some of the long-duration GRBs thus seems solid. We expect the supernova features to continue strengthening with time relative to the power-law continuum of the GRB afterglow. P.S. This information also appears in IAUC 8114, but has been reposted here for the benefit of those GCN subscribers who do not read the IAU Circulars. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2133 SUBJECT: Superluminal motion in GRB 030329 (Correction) DATE: 03/04/10 17:19:52 GMT FROM: Arnon Dar at Technion-Israel Inst. of Tech Arnon Dar (Technion) and Alvaro De Rujula (CERN) report: We use the infamous Cannonball model (CB model) of GRBs to predict the superluminal motion of the source of the radio afterglow (AG) of GRB 030329 (GCN 1985, 1997), potentially observable with the VLBA (see, e.g. GCN 2129). The CB model has been succesful in describing GRB 030329 and its AG, in predicting the supernova (SN) contribution to the AG, and even the date at which the SN was to be convincingly seen [1]. In the CB model, the cannonballs responsible for the GRB and the AG light move superluminally in the sky, as they travel away from their projenitor SN. THIS MOTION MAY BE OBSERVABLE IN THE RADIO AG, IF ITS LOCATION IS FOLLOWED AS A FUNCTION OF TIME [2]. The SN cannot be currently seen in the radio, so that it is the motion of the radio-AG source (the CB) that one may try to observe. In the case of GRB 030329 there were two CBs, one of which dominates the AG after t ~ 1 day. Using the parameters of this CB determined in [1] (initial Lorentz factor 1477, viewing angle 2 mrad, and deceleration parameter 476 kpc) and Eqs. (30, 31, 41) of [3] we obtain the angular distances "alpha" (in mas) of the dominant CB to the SN as a function of "t" (observer's time in days). For the current cosmology (Omega_Lambda=0.7, Omega_Matter=0.3, H_0=75 km/s/Mpc; and for z=0.1685, so that the angular distance is 0.64 Gpc) some representative results are: (t, alpha): (0,0); (1,0.22); (2.7,0.49); (5,0.74); (10,1.1); (30,1.9). This means that from day 2.7 to day 10 the radio source may have moved 0.6 mas, and from day 10 to day 30 it may move an extra 0.8 mas. Such motion may be observable with the VLBA. * mrad in GCN 2132 was corrected to mas [1] Dado et al. astro-ph/0304106. [2] Dar and De Rujula, astro-ph/0008474. [3] Dado et al. 2003 A&A 401, 243. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2142 SUBJECT: OT GRB 030329: early spectrum DATE: 03/04/16 16:26:08 GMT FROM: Vladimir Sokolov at SAO RAS T. Fatkhullin, V. Komarova, V. Sokolov (SAO RAS), V. Kurt (ASC RAS), A. Cherepashchuk (SAI MSU), K. Postnov (SAI MSU), V. Reshetnikov (AI SPBU), Alberto J. Castro-Tirado (INTA, Madrid and IAA, Granada) report: 8 spectra of OT GRB 030329 (Peterson & Prise, GCN 1985; Torii GCN 1986) were obtained under the program "Optical identification of gamma-ray burst sources" (observer A. V. Moiseev, LSPEO SAO RAS) on the night of 29/30 March 2003 (29.934 - 30.004 UT) with the SAO RAS 6-meter telescope at the Northern Caucasus, 0.45 - 0.52 days after the detection of GRB 030329 on Mar. 29.484 UT (G. Ricker et al, IAUC No. 8101). The observations were carried out with the integral field spectrograph (Multi Pupil Fiber Spectrograph, MPFS http://www.sao.ru/~gafan/devices/mpfs/mpfs_main.htm ) The 4x2 (sums of 2 consequent) spectra and additional info can be seen at anonymous FTP-site: ftp://ftp.sao.ru/pub2/grb/GRB030329/ With consideration for z=0.168 the first spectra of the OT GRB 030329 remind the very first spectrum of SN 1987A beginning with lambda=3425A, (Danziger et al, 1987, A&A, 177, L13; Menzies et al. 1987, MNRAS, 227, 39P) The same spectral behaiour of OT is confirmed by simultaneous UBVRI observations with the 1-m (Zeiss-1000) of SAO RAS starting from March 29.717 to 30.015 (UT). The data are being processed for more accurate calibration. A possible interpretation (V.Sokolov): Perhaps, such a behaviour of the very first spectra of OT GRB 030329, as well as the case of SN 1987A, could be explained by the fact that the burst of supernova related to the burst of a compact massive star and recorded in the very beginning of its GRB evolution was observed in detail for the second time. The physics of the early SN brightness peak can be related to the exit of a shock wave (or a jet?) onto the surface of a compact pre-supernova. (e. g. E. Grassberg, V. Imshennik and D. Nadyozin, 1971, Astroph. Space Sci., 10, 28). Though the difference between the types of SN 1987A and SN 2003dh (K. Stanek, T. Matheson, P. Garnavich et al. astro-ph/0304173), and their pre-supernovae should be certainly taken into consideration. We are grateful to our colleagues from the Laboratory of Spectroscopy and Photometry of Extragalactic Objects for their kind assistance in the spectral observations with the 6-meter telescope of SAO RAS. This message may be cited." %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2144 SUBJECT: GRB030329, UBVRI polarimetry, R-polarization DATE: 03/04/17 10:47:04 GMT FROM: Alexei Pozanenko at IKI, Moscow Y.Efimov, K.Antoniuk, V.Rumyantsev (CrAO) and A.Pozanenko (IKI) report: We have performed linear polarization observations of the optical counterpart to GRB030329 (Peterson and Price, GCN 1985; Torii, GCN 1986) and a reference star (RA=161.153362, Decl=+21.449663, Henden, GCN 2082) with 125 cm reflector (AZT-11) equipped with double beams UBVRI polarimeter. The observations were done on March 29 between 0.76689 and 0.9230 UT (JD2452728.2669 - 2452728.4230) at moderate sky condition and sometimes variable transparency. Also the reference star appears to be an eclipsing binary (J. Fitzgerald & J. Orosz, GCN 2056, 2070). However it can be considered as a reference star with a sufficient accuracy because of both the simultaneous observation of the star by V.Rumyantsev et al. (GCN 2005) with accuracy better than 0.02mag @ 180 s and orbital period estimation (GCN 2070) show that the star was far from eclipsing phase. The preliminary analysis of UBVRI photometric data shows no significant color variability of the OT, which is in agreement with the prediction of color behavior for "standard" afterglow models. More detailed analysis is in progress. Polarization measurements were corrected for instrumental effects. The weighted mean of reported polarization degree and position angles are derived from the normalized Stokes parameters. The data obtained for OT and reference star are presented below. Indicated in the table are: fractions of Julian Day JD-2452827, filter, polarization parameters (degree P and position angle PA), their mean errors ME, and the duration DT of measurements in minutes. We found that the polarization in R filter may be considered as marginally detected. The interstellar polarization in the direction of GRB 030329 is less then 0.2% according to interstellar polarization data at high galactic latitude reported by Berdyugin et al. (2001,A&A, 372, 276). The polarization of the reference star combined from measurements in two nights (29 and 30 March, 2003) significantly differs from that found for OT of GRB030329. Mid time, (GRB 30329) Date: March, 29, 2003 JD-2452729 FILTER P (%) ME PA ME DT 0.3261 R 0.90 0.39 109 12 86 (Reference star), Combined data March, 29-30, 2003 FILTER P ME PA ME DT R 0.33 0.17 174.2 13.7 Detailed polarization analysis in all UBVRI filters is in progress. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2145 SUBJECT: OT GRB 030329: early UBVRcIc spectral evolution DATE: 03/04/17 14:09:19 GMT FROM: Timur Fatkhullin at SAO RAS T. Fatkhullin, V. Komarova, V. Sokolov (SAO RAS), V. Kurt (ASC RAS), A. Cherepashchuk (SAI MSU), K. Postnov (SAI MSU), V. Reshetnikov (AI SPBU), Alberto J. Castro-Tirado (INTA, Madrid and IAA, Granada) report: A part of the results of the UBVRcIc observations with the 1-m (Zeiss-1000) of SAO RAS at two epochs on March, 29 and the next two nights are now presented at our anonymous FTP-site: ftp://ftp.sao.ru/pub2/grb/GRB030329/ One can see the evolution of the early broad-band UBVRI spectra. In addition, comparison with the MPFS spectra (see GCN #2142) allows us to perform more precise flux calibration of these spectral data. Sorry! More correct reference quoted in GCN #2142 is E. Grassberg, V. Imshennik and D. Nadyozhin, 1971, Astroph. Space Sci., 10, 28 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2163 SUBJECT: GRB030329: optical polarization DATE: 03/04/22 20:50:48 GMT FROM: Antonio Pereyra at IAG-U.Sao Paulo A.M. Magalhães, A. Pereyra, T. Dominici and Z. Abraham (IAG, U. of São Paulo) report: We have obtained R band imaging polarimetry of GRB030329. The observation was performed with the IAGPOL imaging polarimeter and the IAG-USP 60cm telescope, at the Laboratório Nacional de Astrofísica site. The observation spanned the period UT 01:06 to 01:51 on 31 March, 1.519 - 1.592 days after the event, and was made through less than ideal sky conditions. The double-beam technique provided by a calcite plate analyser ensured however that useful polarimetric data could still be obtained. We have measured the following linear polarization for GRB030329: P = [1.974 +- 0.477] %, position angle = 83.2 degrees. (The position angle is already in the equatorial system, increasing from North to East.) As a comparison, we have obtained much smaller polarization for field objects. In particular, for USNO A-2.0 1050-6351075 (object 'A' in Rumyantsev et al, GCN 2005) and 1050-6349885, we have obtained the following linear polarization values: [0.58 +- 0.11] at 66deg and [0.06 +- 0.12] at 21deg, respectively. This low foreground polarization is consistent with the very low foreground reddening towards the field (E(B-V)=0.025, Schlegel et al. 1998). Dilution of the GRB intrinsic polarization by the much fainter (Blake & Bloom GCN 2011) host galaxy should be negligible. Polarization within the host galaxy interstellar medium seems unlikely due to the small internal extincion (Caldwell et al. GCN 2053); this should be settled by variability studies and spectropolarimetry. We conclude that a substantial fraction of the GRB030329 polarization is intrisic in nature. This strongly suggests that GRB030329 is non-spherically symmetric, lending further credence to the asymmetric fireball scenario (in combination with a physical process that produces polarization, such as synchtron radiation). The position angle above should be correlated with the object's beam or jet orientation on the sky. It would be interesting to see whether a similar position angle is present in forthcoming resolved radio observations of the source. This message may be cited. [GCN OPS NOTE (22Apr03): The circular was originally submitted on 14 Apr 03, but was delayed due to email address mismatch.] %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ITLE: GCN GRB OBSERVATION REPORT NUMBER: 2176 SUBJECT: GRB030329 observed as a sudden ionospheric disturbance (SID) DATE: 03/04/28 22:38:19 GMT FROM: Doug Welch at McMaster U,PhysAstro. P.W. Schnoor, D.L. Welch, G.J. Fishman and A. Price report, on behalf of the AAVSO GRB-SID Network, on the detection of GRB030329 as a sudden ionospheric disturbance (SID), observed by Peter Schnoor of Kiel, Germany. A disturbance of the Earth's ionosphere was observed coincident with the HETE detection of GRB030329. This SID was seen as an increase in the signal strength from a Low Frequency (LF) radio beacon received in Kiel, transmitted as a time signal from station HBG (75 kHz) near Geneva, 920 km from the receiver. (Note: This is not a radio detection of GRB030329; this disturbance was caused by the prompt X-rays and/or gamma-rays from GRB030329 ionizing the upper atmosphere and modifying the radio propagation properties of the Earth's ionosphere.) Due to the sub-burst longitude and latitude and the geographical distribution of LF/VLF beacons and monitoring stations, this was the only recording (positive or negative) where GRB030329 illuminated the ionosphere along a signal path. Several plots of the SID detection, including one with an overlay of the HETE X-Ray lightcurve are available at the URL http://www.qsl.net/df3lp/projects/sid/index.html Additional details of the observation are also available at this site. While this type of observation is not yet quantitative, future observations of enough GRBs may allow a quantitative measurement to be made of the prompt, total ionizing flux (X-rays and gamma-rays) incident at the Earth over an extremely broad energy range. This measurement is not now attainable with any single spacecraft and will not be, until the launch of the NASA GLAST mission in 2006. Previously, at least three other transient, high-energy sources have produced detectable ionospheric disturbances, as measured with VLF receivers: GRB830801 (Fishman and Inan, Nature v.331, p.418, 1988); XRF 020427 (GCN 1394), and the Aug. 27, 1998 super-flare from SGR 1900+14 (Inan, et al., Geophys. Res. Lett., v.26, p.3357, 1999). The AAVSO SID-GRB network is a worldwide network of observers monitoring VLF and LF beacons for SIDs of non-solar origin. The AAVSO Solar Committee has been monitoring and reporting solar-induced SIDs since the 1950's. This group intends to continue and expand this monitoring network. This message may be cited.