TRIUMF EEC July 8th 2005 1

Letter of Intent: XXXXI

Alex MurphyAlex Murphy

Study of Reactions Study of Reactions Important to Synthesis of Important to Synthesis of

44Ti in Core Collaspe 44Ti in Core Collaspe SupernovaeSupernovae

…good evening from Edinburgh

TRIUMF EEC July 8th 2005 2

Core Collapse SupernovaeCore Collapse Supernovae

Science Case ‘Easy’ to make

Supernovae are… Some of the most powerful explosions in the

Cosmos Some of the most scrutinised objects in the

Universe Responsible for production of many heavy

elements Responsible for shaping our local distribution of

stars

There is consensus on the basic mechanism But! The best simulations still don’t explode!

Extremely complex Need a good diagnostic

SN1987A

M1 – The Crab44Ti !

TRIUMF EEC July 8th 2005 3

Core CollapseCore Collapse

Massive star (>10–12 M) Stellar evolution onion-skin-like structure At maximum of BE/A, thermal support lost Core collapses Shock wave passes through Si layer above core Dissociation back to n, p, and …Nuclear statistical equilibrium… …Alpha-rich freeze out Dominant site for 44Ti production Key reactions to be studied*

40Ca() – E1024 44Ti() 44Ti(,p) – This work 45V(p,) – This work Triple

* (The et al ApJ 504 (1998) 500)

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44Ti production44Ti production

Amount ejected sensitively depends on location of the ‘mass cut’

Material that ‘falls back’ is not available for detection

44Ti yield a sensitive diagnostic of the explosion mechanism

Thus, VERY useful for models to make comparisons against

What’s more, it’s (relatively) easily observed

Gamma-Ray observation 1.157 MeV INTEGRAL & other missions

Meteoritic data Enrichment of 40Ca in type X grains

Timmes et al. (1996)

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Proposed researchProposed research

Take advantage of unique future ISAC beams 44Ti(,p)47V – direct measurement

Gas/implanted target Trilis, CSB LEDA/CD Not measured before at astrophysical energies - extrapolation of previous results suggests

it’s eminently feasible (@ 10^7 pps). 45V(p,p)45V – resonant elastic scattering

Knowledge of 46Cr, precursor to 45V(p,)46Cr Trilis, CSB CH2 target LEDA/CD Unmeasured. SM/TES suggests ‘feasible’ (@ 10^7 pps).

45V(p,)46Cr Trilis, CSB DRAGON Use (p,p) as guide.

Coordinated approach

TRIUMF EEC July 8th 2005 6

UK Grant applicationUK Grant application

A request has been made to UK’s EPSRC specifically based on this work, at this facility

Request is for 33 months of PDRA + Travel Panel meets 27/7/05 Referees’ reports…

Very positive feedback. Confident this will be funded

TRIUMF EEC July 8th 2005 7

Purpose of this LoI…Purpose of this LoI…

Proposed research requires: Charge state booster Laser ion source (TRILIS) Development of 44Ti and 45V beams

Many thanks for your time…

And sorry I couldn’t e there

And many thanks to Marialuisa!!!!