The SN-GRB Connection from the SN perspective Elucidating the SN-GRB Connection: Host Galaxies and Metallicities The SN-GRB Connection from the SN perspective Maryam Modjaz Miller Postdoc Fellow/UC Berkeley STScI, 04/30/2008

Fellow Stellar Death Detectives Bob Kirshner (Former Advisor, Harvard University) M. Hicken, S. Blondin, P. Challis, M. Wood-Vasey, A. Friedman (Harvard/CfA) K. Z. Stanek, J. L. Prieto (Ohio State), T. Matheson (NOAO) L. Kewley (Hawaii), P. Garnavich (Notre Dame) J. Greene (Princeton) J. Bloom, D. Kocevski, D. Starr (UC Berkeley), C. Blake (CfA)

Outline: SN-GRB Connection 1) Introduction & Relevance: - Key Question: Production conditions for SN-GRB? SN Ic with and without GRBs 2) Sample and Observations of SN Ib/c & SN-GRB: - Are only SN-GRBs aspherical ? Probably NO 3) Environments of SN Ib/c and GRB-SN: - Higher Progenitor Mass for SN-GRB? Probably NO - Low Metallicity for SN-GRB? Probably YES! 4) Conclusion & Future Prospects

Outline: SN-GRB Connection Introduction & Relevance: Definition, Massive Star Deaths SN-GRB connection, Outstanding Question Sample and Observations of SN Ib/c & GRB-SN 3) Environments of SN Ib/c and GRB-SN & the SN-GRB connection 4) Future Prospects & Conclusion

What is a Supernova? Just Google it:

What is a Supernova, really? What is a Supernova (SN), really? What is a Supernova, really? Brilliant Explosion of a star SN 1994D (Credit: P. Challis) SN 1994D (Credit: P. Challis)

SN Classification Spectra: Stripped-Envelope SN Thermonuclear SN Core-Collapse SN HeI Stripped-Envelope SN Broad lines large expansion v large KE (1052 erg) “Hypernova”

DEATHS OF MASSIVE STARS Progenitor Models of SN Ib and Ic 1) Single massive (> 30 M) Wolf-Rayet (WR) stars (e.g., Maeder & Conti 2004; Woosley et al. 1995) Mass Loss: during MS & WR stage a) metallicity-dependent winds (Crowther 2007) b) or LBV-type eruptions (Smith & Owocki 2006) 2) He stars (8-20 M) in binaries (Podsiadlowski et al. 2004) Pre-Explosion Observations of SN Ib/c: Cannot differentiate between 1) and 2) (Gal-Yam et al. 2005, Maund et al. 2005, Crockett et al. 2007) Interacting SN Ib: WR-Star w/ outburst 2 yr prior

DEATHS OF MASSIVE STARS SN Rates: 1 SN / (100 years) / (MW-galaxy) How common are SN Ib/c? Local rate: ~15-20% of all SN ~30% of CC-SN Broad-lined SN Ic: ~5-10% of all SN Ib/c (Cappellaro et al 1999, Guetta & Della Valle 2007, Leaman et al. in prep)

Massive Stellar Evolution Janka et al. (2005): 3D simulations, follow explosion Woosley, Heger & Weaver (2002) Woosley: Star undergoes successive stages of fusion in the core [H, He, C, Ne. Oxy, Si] & shells all hydrostatic burning phases - > e capture & photo-disintrigation Janka: Explosion only (neutrino-driven),15 M_sun, assuming initial model of spherical symmetry and non-rotating. Accretion onto nascent NS: bipolar nature. Blue: SN shockwave, Red: Accretion, Grey: Neutrino-heated, hot ejecta Nucleosynthesis: massive stars; also r-process synthesis possible before explosion for low-Z & massive stars (PopIII): alpha-rich elements

Gamma-Ray Bursts: Extreme Explosions Short GRB Long GRB 2s 2 “Types”: 1) Short-hard GRBs 2) Long-soft GRBs (LGRB): - Non-thermal & dramatic variability: t/t << 1 - Relativistic outflow: g~1-1000 - Highly collimated jets: ~5-10o

SN-LGRB Connection Spectroscopic ID: SN Ic-bl GRB980425/SN98bw z=0.0085, D=58 Mpc (Galama et al. 1998) 2) GRB030329/SN03dh z=0.1685 (Stanek et al. 2003, Hjorth et al 2003) 3) GRB031201/SN03lw z=0.1005 (Malesani et al.2004) 4) XRF020903 z=0.25 (Soderberg et al. 2005, Bersier et al. 2006) 5) GRB060218/SN06aj z = 0.0335, D=160 Mpc (e.g.,Campana et al, Mirabal et al., Modjaz et al. 2006) Stanek et al. (2003), Matheson et al. (2003) [see also Review (Woosely & Bloom 2006)] 98bw: E_iso = 10^47-10^48 erg Nearby GRB: low-luminosity, more common (~10-103x) than cosmological GRBs (Cobb et al., Soderberg et al., Guetta & Della Valle 2006, etc)

Collapsar Model Core Collapse SN Ib/c Stellar Material forms accretion disk around rapidly rotating BH: accretion lifetime ~ GRB duration (1-103 s) Relativistic Jet able to leave star (Zhang et al. 2004) E~1051 - 1054 erg Image: SN shock visible as blue: The passage of the jet initiates a shock that propagates to lower latitudes and eventually exploded the whole star Initial SN shock seen in pale blue at R=2x10^10cm SMALL PICTURE: Jet after 8sec; center of 15 WR star, Lorenzfactor ~200 For initial collimation of 10 deg MacFadyen, Woosley & Heger (2001)

SN-GRB CONNECTION What fraction? What distinguishes SN with GRB from 20/25 of broad-lined SN Ic have NO observed GRB viewing angle effects? - Probably NO: <10% of all SNIb/c are off-axis GRBs (Soderberg et al. 2006) - Rates (Podsiadlowski 2004, Guetta & della Valle 2007) What distinguishes SN with GRB from SN w/o GRB? Physical Reason? RATES: Soderberg et al (2006)

RELEVANCE of SN Ib & SN Ic Deaths of Massive stars Constrain explosion energetics and element synthesis, progenitors and remnants Connection of SN Ic-bl to GRBs What is the range of SN Ic & SN Ic-bl properties? How aspherical are (normal) SN Ib/c explosions? Potential contamination of high-z SN Ia searches by SN Ic (Clocchiatti et al. 2000, Homeier 2005) However, only a handful of well-studied objects Matheson et al 2001 (mostly spectra) Richardson et al. 2006 (pre-CCD SNe) NEXT STEP: homogeneous & densely covered data set

Outline: SN-GRB Connection Introduction & Relevance Sample and Observations of SN Ib/c & GRB-SN: SN - Sample (2004-2007) Analysis: E.g. Are SN round? 3) Environments of SN Ib/c and GRB-SN & the SN-GRB connection 4) Future Prospects & Conclusion

NEARBY CFA SN FOLLOW-UP Optical Spectroscopy: FAST on FLWO 1.5m 3–4 spectra/night, ~300 spectra/year Reduced in the same manner Optical Photometry (UBVr’i’): FLWO 1.2m 3-4 SN/night, templates, standard star obs NIR Photometry (JHKs): PAIRITEL 1.3m 3-4 SN/night Late-time (>3 months) Spectra: MMT (AZ), Magellan (Chile), Gemini-North (Hawaii, GN-2005B/2006A) 1.5m 1.2m 1.3m 6.5m MMT

IR Light Curves Yoshii et al 2004 PAIRITEL: automated, ex-2MASS, 1.3 m telescope, dedicated IR facility (Bloom, Szentgyorgyi, et al) Well-understood 2MASS camera and characteristics, photometric calibration via 2MASS Few NIR LCs for SN Ib/c (e.g., SN 2004aw: Taubenberger et al. 2006)

Representative Data t Sample (> 10 epochs of Optical Photometry or Spectra): 11 SN Ib/IIb 10 SN Ic 1 GRB-SN 1) Doubles world supply of well-observed SN Ib/c 2) Peculiar objects: 05bf, 06jc

Photometry: 2004-2007

Theory: Light curves Spectra Mejecta SN Ejecta: v(r)r 56Ni KE Flux Credit: S. Blondin t LC width ejecta KE-3 Line width ejecta KE1/2

SN2006aj/GRB060218 z = 0.0335, Weak GRB Afterglow 98bw GRB-SN short rise time (10 days) 98bw GRB-SN Time- stretched 98bw Diversity in SN-GRBs !! Modjaz et al. 2006

Modeling & Implications of GRB060218/SN2006aj Data from Pian et al (2006) Mazzali et al. (2006): Ek ~ 2 x 1051 erg, M ~ 25 M Low-z GRB(-SN): low-lum., larger q, more common (~10-103x) than cosmological GRBs (Cobb et al., Soderberg et al., Guetta & Della Valle, etc)

Analysis: a) Distribution of MV SN Ia (@ peak) SN Ib/IIb SN Ic SN Ic-bl MV(@peak) Large range of mags (~4 mags) 2) SN Ib/IIb on average fainter than SN Ic 3) Broad-lined SN Ic not necessarily more luminous than normal SN Ib/c Richardson et al. (2006) & my sample

Analysis: Luminosity & LC Modjaz et al. in prep 1) No Luminosity - LC shape relationship for SN Ic 2) GRB-SN & broad-lined SN Ic have similar spectra GRB-SN appear more luminous (~2 mag)

Late-time Line Diagnostics - GRB SN 2003jd (SN Ic-bl) : Off-axis GRB? (Mazzali et al. 2005) Probe deeper into SN ejecta than early-time spectra: 1) Line Ratios: state of core before explosion (Foley et al. 2003, Maeda et al. 2005) 2) Line shape: geometry of explosion (Mazzali et al. 2005, Maeda et al. 2006, Valenti et al, in prep) [O I] 6300,6363 [Ca II] 7319,7324 [Mg I 4571 SN 2004gk (SN Ic)

Late-time Spectra (~10 SN Ib/c) Modjaz, Kirshner, & Challis (2008b)

Asphericities are common in SN Ib/c Maeda et al. (2008) Gerardy et al. (2002) - Oxygen ring ejection in SNR E0102.2-7219 (Tuohy & Dopita 1983, Blair et al. 2000) Modjaz, Kirshner, & Challis (2008b)

Outline: SN-GRB Connection Introduction & Relevance: Sample and Observations of SN Ib/c & GRB-SN 3) Environments of SN Ib/c and GRB-SN & the SN-GRB connection: Blue light (proxy for mass) Abundance 4) Future Prospects & Conclusion

SN-GRB distinction: Environs Fruchter et al (2006): - high-z GRB (0.2 < z < 1.0) -“GRBs are concentrated on the brightest regions of their hosts.” SN II (Non-SN Ia) LGRB

Environmental Clues Fruchter et al (2006) Local SN Ic and GRB have similar locations compared to host galaxy light Similar (large) progenitor masses - Additional ingredient needed for GRB production Fruchter et al (2006) LGRB SN Ic SN Ic-bl Kelly, Kirshner, & Pahre (2008, submitted)

GRB Host galaxies Fruchter et al. (2006): GRB hosts are less luminous & smaller than SN II hosts SN II (Non-SN Ia) LGRB

Host galaxies of LGRBs Low-metallicity, subluminous host galaxies: Nearby GRBs not unbiased tracers of star formation Low-metallicity, subluminous host galaxies: @ low-z (Sollerman et al. 2005, Gorosabel et al 2005, Modjaz et al. 2006, Thoene et al 2007,Wiersama et al 2007 ) Possibly @ high-z (Le Floc’h et al 2003, Fruchter et al. 2006) Stanek, .., Modjaz et al (2007)

Stellar Evolution @ low Z Progenitor Stars of GRB: Rotating massive stars @ low Z with Taylor-Spruit Dynamo High Angular momentum in core Removal of H: Mixing of H (Hirschi et al. 2005) Binary interaction Massive core (MacFadyen & Woosley1999; Yoon & Langer 2005; Heger & Woosley 2006) Prediction: SN without GRB have higher Z Ingredients for SN-GRB

Metallicities of Broad-lined SN Ic Sample: 12 broad-lined SN Ic w/o GRBs (z < 0.15) Data: Own & Archival (SDSS) Stellar Light Removal Oxygen Abundance estimates from strong line diagnostics (Kewley & Dopita 02 & others) Central & SN-position measurements Uncertainty budget Modjaz et al. (2008)

Local abundances of GRB-SN and broad-lined SN Ic Local SDSS galaxies (Tremonti et al 2004) in KD02 scale SMC LMC SDSS: z< 0.2, oxy~8.6 = 0.5 Z if Z_sol = 8.9 0.3 dex = FACTOR of 2 0.5 dex = FACTOR of 3 0.7 dex = FACTOR of 5 Z-Offset not due to selection effects Importance of galaxy-impartial SN surveys, e.g., PanSTARRS! Modjaz et al (2008)

Z-Offset independent of Z-Diagnostic (Kewley & Dopita 02) (McGaugh 91) (Pettini & Pagel, Te ) (McGaugh 91) (Pettini & Pagel, Te ) “cut-off metallicity”: 0.2- 0.6 Z Most favored: 0.3 Z SN w/o GRB SN w/ GRB KS-Test: 3% 4% 3% KS-Test: 3% 4% 3%

Do GRB host galaxies follow L-Z? No at low z Savaglio et al (2006) (GHostS conference proceeding) GRB hosts 0.4 < z < 1 Probably No at higher z Kewley et al. (2007) Brown et al. (2008) Savaglio:

Metallicities Via Absorption @ higher Redshift Not comparing same element! Need NIR spectra for high-z GRBs to observe emission lines Prochaska et al (2007): No low-Z preference of GRB-DLA vs. QSO-DLA

“Long (?)” GRBs without SN Or: like Long GRB? (Thoene et al. 2008) GRB060605: Short GRB-like (Levesque & Kewley 2007) GRB060614 (Gal-Yam et al, Fynbo et al, Della Valle et al, 2006) GRB060614 GRB060605 (Fynbo et al. 2006) But really Long GRBs? GRB Identity Crisis! Environmental studies might help!

Outline: SN-GRB Connection Introduction & Relevance: Sample and Observations of SN Ib/c & GRB-SN 3) Environments of SN Ib/c and GRB-SN & the SN-GRB connection 4) Future Prospects & Conclusion

Conclusions SN-GRB Connection: Association between core-collapse SN (broad-lined SN Ic w/o H and He) and LGRBs well-established BUT: Why do some SN have GRBs and some not? Spectroscopic & photometric dataset for SN Ib and Ic is comprehensive, extensive & well time sampled Asphericity in (even) normal SN IIb/Ib/Ic & not only in SN-GRB Sites of broad-lined SN Ic (w/o GRB): higher oxygen abundance than those of SN-GRB: low Z key-factor for nearby GRB-SN FUTURE: - GRBs as beacons for galaxies - Environments of SN

Future Prospects Chemical abundances for all SN Ib & SN Ic @ the explosion sites Look for Trends between SN Properties & Abundances (Woosley & Janka 2005) Differentiate between Progenitor Models of SN Ib/c: 1) Single massive (> 30 M) Wolf-Rayet (WR) stars Mass Loss: during MS & WR stage via metallicity-dependent winds PREDICTION: ZSNIc > ZSNIb 2) He stars (8-20 M) in binaries PREDICTION: ZSNIc ~ ZSNIb SN Ic ? SN Ib ?

Bridging low & high redshift Savaglio et al. (2008, submitted)

Massive Star Evolution Conti Scenario (Maeder & Conti 1994, Massey 2003) ~ 8>M>20 Mo : OB RSG BSG SN ~20>M>25 Mo : O RSG WN SN ~25>M>40 Mo : O RSG WN WC SN ~40>M>85 Mo : O WN WC SN M>85 Mo : O LBV WN WC SN (for Galactic metallicity) WN: no/little H, strong He, N Wolf-Rayet Stars WC: no N, strong C, O, some He Mass Loss: During MS & WR stage Nature of Mass Loss?

MAPPING between SN-type & Progenitor Attempts: a) Theoretical b) Observational Heger et al (2003): Single non-rotating Stars Mprog (Msol) Metallicity Gal-Yam et al. (2006)

Theoretical Modeling Ken Nomoto & collaborators

LC of 2003dh

IR Photometry: 1) Precision E.g., SN 2005hg (Ib) 2MASS stars SN

“Maverick”: SN 2005bf (Ib-pec) Tominaga et al (2005) See also Folatelli et al. (2006) Days after UT March 31 2005

“Maverick”: SN 2005bf (Ib-pec) M. Modjaz Tominaga et al (2005): 56Ni ~ 0.3 Msun Mej~6-7 Msun , Mprog~25-30 Msun, NS remnant He lines

SN2006jc (Ib-n) Days after B max See also Foley et al. (2007), Pastorello et al. (2007), Smith et al. (astro-ph) NIR Excess -> Dust emission

Importance of NIR contribution F (NIR)/F(bol) SN 2005bf J. Deng, M. Modjaz

IR photometry Elias et al. (1986),Yoshii et al (2004)

Enigmatic GRB/XRF 060218 Campana et al 2006 Campana et al 2006

GRB020618 in Radio & Xray Soderberg et al 2006

Spectral Library Spectra & Lightcurves: Spectral Sequence SN identification: SN Ic very similar to SN Ia ! All Spectra with phase info used in SNID (Blondin & Tonry 2007) SN identifications via email & available at http://cfa-www.harvard.edu/cfa/oir/Research/supernova/RecentSN.html

SN Ia vs. SN Ic At maximum light At two weeks past maximum Blondin & Tonry (2007)

SN Ia vs. SN Ic At maximum light At two weeks past maximum Blondin & Tonry (2007)

Grotrian diagram for Fe II (b-b only) Line Transitions Grotrian diagram for Fe II (b-b only) Gehren et al. 2001

b) cont’d: Include “all SN-GRB” ? -1 mag -- 1.9 mag = Ferrero et al 2006

Late-time Data: a) SN2005bf Blueshift: ~2000 km/s OI: double-peaked Moxy> 0.1- 1.1 Msun Assuming: T~ 3000-4500 K -ne ~106 - 108 cm-3 H: not blue-shifted, FWHM = 9000 km/s 0.2 - 0.3 Msun for thick shell (if v = 0.2-0.5 v) at R=2x1016 cm Predicted: LX~4 x 1039 erg s-1 From WR Wind?

SN2006aj/GRB060218 Kocevski et al (2007) Modjaz (2007)