Presentation is loading. Please wait.

Presentation is loading. Please wait.

A Radio Perspective on the GRB-SN Connection Alicia Soderberg May 25, 2005 – Zwicky Conference.

Similar presentations


Presentation on theme: "A Radio Perspective on the GRB-SN Connection Alicia Soderberg May 25, 2005 – Zwicky Conference."— Presentation transcript:

1 A Radio Perspective on the GRB-SN Connection Alicia Soderberg May 25, 2005 – Zwicky Conference

2 Gamma-Ray Bursts highly relativistic (  ~100) jets (  ~ few degrees)  -ray emission mildly relativistic (  <10) ejecta produce “afterglow” emission imply central engine spherical explosion produces non-relativistic (  <1) optical SN emission (Type Ibc) Rate: ~2.5 x 10 2 Gpc -3 yr -1

3 Type Ibc Supernovae ? NO H in optical spectra (10%) NO  -ray emission NON-relativistic,  <1, synchrotron emission from mildly asymmetric ejecta NO evidence for central engines spherical explosion drives non-relativistic optical SN Rate: 4.8 x 10 4 Gpc -3 yr -1 ~ 0.5 % of SNe Ibc associated with GRBs

4 GRBs ? SNe Ibc Spherical + Jet Framework connection

5 (Galama et al., 1998; Pian et al. 2000) z=0.0085 (~36 Mpc) SN1998bw discovered within BeppoSAX error box for GRB 980425  Two key probes: Optical & Radio GRB980425 and Type Ic SN1998bw “A GRB/SN Connection”

6 GRB980425 and Type Ic SN1998bw “A luminous local SN” Optical emission requires: ~ 0.5 M  Nickel v ~ 60,000 km/s (Iwamoto et al.1998; Woosley et al. 1999) (Galama et al. 1998)

7 8.5 GHz E ~ 5 x 10 49 erg  ~3 ejecta (Kulkarni et al.1998; Li & Chevalier 1999) What fraction of SNe Ibc are like SN1998bw? GRB980425 and Type Ic SN1998bw “The most luminous radio SN”

8 RADIO is most sensitive to relativistic ejecta 1. Synchrotron emission traces the fastest ejecta 2. The synchrotron peak is near/below the radio band. 3. Higher frequencies dominated by other processes. Observe EVERY (optically selected) SN Ibc within 100 Mpc Caltech/NRAO/ATCA Radio Type Ibc SN Survey

9 VLA Survey of Type Ibc Supernovae Results: 11 detections 82 upper limits (Soderberg et al. 2005; Berger et al. 2002,03; Kulkarni et al. 1998) Radio bright SN Ibc are rare and diverse.

10 Equipartition Energy and Velocity Out of 93 SNe, none like SN1998bw and/or GRBs < 1% GRB/SN

11 Radio Analysis of SN 2003L (Soderberg et al., 2005a) Detailed Modeling:  E ~ 10 49 erg  v ~ 0.2c  r ~ t  B ~ r -1  n ~ r -2  M dot ~ 10 -5 M  /yr

12 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc No  -rays seen

13 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc Afterglow begins

14 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc

15 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc Type Ibc SN!

16 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc

17 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc

18 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc

19 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc

20 log (time) log (F ) “Hidden” GRB Jets in Local SNe Ibc

21 log (time) log (F ) t ~ 1 week to few yrs “Hidden” GRB Jets in Local SNe Ibc

22 Constraints on Off-Axis GRBs Out of 53 SNe Ibc, None house GRBs < 2% GRB/SN Broad-lined events are NO exception < 20% GRB/BL (Soderberg et al. in prep)

23 OPTICAL: Peak SN magnitudes (Soderberg et al., 2005c)  GRB-SNe do NOT necessarily synthesize more 56 Ni than local SNe Ibc.

24 Conclusions & Future Progress Radio SNe Ibc are rare and diverse. Their optical properties are similarly diverse and overlap with GRBs ~10 % are radio bright < 1% with relativistic ejecta < 2% with off-axis GRB jets ATA will enable further progress, but SN studies will still be limited by optical discoveries. We need MORE small telescope campaigns.

25 Broad-lined SNe Ibc Radio limits imply unusual shock parameters and/or low densities.


Download ppt "A Radio Perspective on the GRB-SN Connection Alicia Soderberg May 25, 2005 – Zwicky Conference."

Similar presentations


Ads by Google