Subaru Users Meeting (January 15, 2009) Light-Echo Spectrum revealed types of Tycho Brahes’s 1572 & Cas A SNe Cas A Blue ： X-ray (CXO) Green ： Optical (HST) Red ： Mid-IR (SST) Tomonori Usuda (SUBARU) Oliver Krause, Stephan M. Birkmann, Miwa Goto (MPIA), Takashi Hattori (Subaru Telescope), Masaomi Tanaka, Ken’ichi Nomoto (Univ. of Tokyo), George H. Rieke, Karl A. Misselt (Steward Observatory) Tycho BGY ： X-ray (CXO) Red ： Mid-IR (SST) White: Near-IR

Subaru Users Meeting (January 15, 2009) Outline 1.Review Galactic Supernova Remnants (SNRs) & Historical Supernovae (SNe) Cassiopeia A (Cas A) Tycho Brahe’s SN Special Observation Tool: Light echo 3.Case 1: Cas A – Observation / Results 4.Case 2: Tycho – Observation / Results 5.Future plans & Conclusion

Subaru Users Meeting (January 15, 2009) DesignationYearType RCW86185II / Ia ? G ? Lupus1006Ia Crab1054II 3C ?II ? Tycho1572Ia Kepler1604Ia / Ib ? Cas A1680 ?Ib / Ic / II ? G ?? Review Galactic Supernova? Kepler G11.2 RCW86 Tycho Brahe Crab Cassiopeia A G1.9

Subaru Users Meeting (January 15, 2009) Cassiopeia A Second youngest SNR known in our Galaxy (cf. G discovered by CXO in 05/13/2008) Well known & studied SNR It might be appeared around 1680, however no historic records (e.g., SN1054: Crab by Teika Fujiwara 『 Meigetsuki 』 ) Q1: What kind of supernova explosion? Q2: Why it was not witnessed in 17 th century?

Subaru Users Meeting (January 15, 2009) Tycho Brahes’s 1572 Supernova Well known & studied SNR Danish astronomer Tycho Brahe found very bright `new star’ in the constellation of Cassiopeia on the evening of 11 th of November in He had observed its brightness, color, and proper motion until March in In 20 th century, the `new star’ = A supernova –Brightness & Color light curve ←→ Theoretical Model of SN –X-ray observations → Spherical symmetry of metal abundance –Radio etc. → No pulser –Optical → Candidate of surviving binary companion of SN 1572 Q: Is SN 1572 really type Ia Supernova? → Classified by only optical spectrum ``Astronomie Populaire” by Camille Flammarion (Paris, 1884)

Subaru Users Meeting (January 15, 2009) How we can solve the mysteries on the past?! Light Echo can go back to the past rewind time

Subaru Users Meeting (January 15, 2009) Light echoes – Rewinding time to historic SN explosions Echo (sound) 2800 ft (850m) 5 seconds

Subaru Users Meeting (January 15, 2009) Light echoes – Rewinding time to historic SN explosions Blue : Light of SN explosion arrived at Earth in Red : Scattered-light echo by dust arrives now.

Subaru Users Meeting (January 15, 2009) "As Professor J.H. Oort has pointed out to us, the illumination of surrounding clouds might become a spectacular phenomenon in the case of galactic supernovae. The search for the illumination of galactic clouds by past suspected supernovae such as Tycho's star and the stars which gave rise to the Crab Nebula and perhaps other nebulosities presents an interesting problem”. By Zwicky Rev. Mod. Phys. 12, 66 (1940) Light echoes – Rewinding time to historic SN explosions Suntzeff SN 1987A

Subaru Users Meeting (January 15, 2009) However… Observation of Light echo is very difficult. Very Faint (Light echo became fainter and fainter day by day) → Even though can detect light echo, difficult to take its spectrum When? Where? How bright? → Just wait and Searching Light echoes – Rewinding time to historic SN explosions Suntzeff SN 1987A Echo geometry Dust cloud SN

Subaru Users Meeting (January 15, 2009) Observations When? Where? How bright? → Monitoring and ToO (Target of Opportunity) → International collaborations with MPIA Calar Alto 2.2m & 3.5m + Wide Optical Camera PI: Oliver Krause (MPIA) → Monitoring & Looking for optical light echo Subaru Telescope 8.3m + FOCAS PI: Tomonori Usuda (Subaru/NAOJ) → Imaging: Re-confirmation of light echo Spectroscopy: Take its optical spectrum

Subaru Users Meeting (January 15, 2009) Case 1: Cassiopeia A

Subaru Users Meeting (January 15, 2009) October 9, 2007 Spectro- scopy Associated scattered light echo by Calar Alto 2.2m & SUBARU 8.2m SUBARU + FOCAS Detect optical light echo! R = 23.4 mag / arcsec 2

Subaru Users Meeting (January 15, 2009)  =2.4nm (  476~989 nm) / Av=3.1 mag Exp time=5.5 hours Results: Spectroscopy Spectral features of Supernovae Broad line width (17,000 km/s) / P-Cygni profile Strong H & He emission lines He IHαHe I Went back in time to detect light that originally arrived at Earth more than 330 years ago.

Subaru Users Meeting (January 15, 2009) Results Typesub-typeSpectral Feature I Ia No Hydrogen lines Strong Si lines Remarkable Fe lines in later phases Ib No Hydrogen lines Remarkable He lines in max period Weak Si lines / No Fe lines Ic No H & He lines Weak Si lines / No Fe lines II Strong H lines Light curve → II-P-type (plateau), II-L-type (linear), II-n-type (narrow) IIb Visible H lines Remarkable He lines

Subaru Users Meeting (January 15, 2009) Comparison with the proto-typical type IIb SN 1993J

Subaru Users Meeting (January 15, 2009) Results Typesub-typeSpectral Feature I Ia No Hydrogen lines Strong Si lines Remarkable Fe lines in later phases Ib No Hydrogen lines Remarkable He lines in max period Weak Si lines / No Fe lines Ic No H & He lines Weak Si lines / No Fe lines II Strong H lines Light curve → II-P-type (plateau), II-L-type (linear), II-n-type (narrow) IIb Visible H lines Remarkable He lines

Subaru Users Meeting (January 15, 2009) Cas A was a type IIb SN & Red Supergiant (13-20 Solar Mass) as progenitor star Comparison with the proto-typical type IIb SN 1993J

Subaru Users Meeting (January 15, 2009) Case 2: Tycho

Subaru Users Meeting (January 15, 2009) N E 30” Results: Imaging a: Calar Alto 2.2m b: Subaru ＋ FOCAS Back box: Previous light echo position in 2006 Red+ mark: Brightest position (R=23.5 mag) → Slit position (2.8”x2.0”) for spectroscopy by FOCAS → Subtraction of sky & nebulosity lines Center of SNR Slit position Shift

Subaru Users Meeting (January 15, 2009) Results: Spectroscopy Remarkable spectral features of Supernovae Broad line width (9,000~12,000 km/s) No H & He lines Strong absorption lines of Si and Fe Hα Si He Optical spectrum of the light that originally arrived at Earth in 1572  =2.4nm (  380~920 nm) / Av=2.4 mag Exp time=2.5 hours (Red) hours (Blue)

Subaru Users Meeting (January 15, 2009) Results Typesub-typeSpectral Feature I Ia No Hydrogen lines Strong Si lines Remarkable Fe lines in later phases Ib No Hydrogen lines Remarkable He lines in max period Weak Si lines / No Fe lines Ic No H & He lines Weak Si lines / No Fe lines II Strong H lines Light curve → II-P-type (plateau), II-L-type (linear), II-n-type (narrow) IIb Visible H lines Remarkable He lines

Subaru Users Meeting (January 15, 2009) Results: Spectroscopy Spectral features of Supernovae Broad line width (9,000~12,000 km/s) No H & He lines Strong absorption lines of Si and Fe → Type Ia Supernova Hα Si He

Subaru Users Meeting (January 15, 2009) Results Typesub-typeSpectral Feature I Ia No Hydrogen lines Strong Si lines Remarkable Fe lines in later phases Ib No Hydrogen lines Remarkable He lines in max period Weak Si lines / No Fe lines Ic No H & He lines Weak Si lines / No Fe lines II Strong H lines Light curve → II-P-type (plateau), II-L-type (linear), II-n-type (narrow) IIb Visible H lines Remarkable He lines

Subaru Users Meeting (January 15, 2009) Type Ia SN = Cosmological distance indicator → Discovery of the accelerated expansion of Universe Luminosity is NOT uniform! Various type Ia Supernova Normal Type Ia SN OverluminousSubluminous Reason why its variety of luminosity? → Accurate cosmological distance indicator? Si Ca Fe Ni Si Ca Fe Ni Si Ca Fe Ni

Subaru Users Meeting (January 15, 2009) Results: Spectroscopy Overluminous type Ia Normal type Ia Subluminous type Ia Tycho was normal type Ia SN

Subaru Users Meeting (January 15, 2009) Unique opportunity to test theories of SN Explosion mechanism d=100 Mpcd = 3.8 kpc 10 arcmin SNe in extra-galaxiesTycho’s SNR Point source

Subaru Users Meeting (January 15, 2009) Spatial Resolved Investigation HighVelocity Ca II

Subaru Users Meeting (January 15, 2009) Conclusions For the first time, spectra of historical Galactic supernovae (Cas A & Tycho) have been secured. Cas A: Type IIb SN & Red Supergiant (13~20 Mo) Why Cas A was not witnessed in 17th century Type IIb SN fade away quickly, poor weather of several days, higher extinction (A v ~8), peak brightness (~3 mag) Tycho: Normal type Ia SN & d=3.4kpc (cf. 2.3~2.8 kpc) Light echoes at different position angles from the source →3D aspect → Spatial structure of SN outburst mechanism

Subaru Users Meeting (January 15, 2009) Mahalo !