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CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl Constraining nova observables: Direct measurement of 33 S(p,  ) 34 Cl in inverse kinematics Jennifer Fallis,

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Presentation on theme: "CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl Constraining nova observables: Direct measurement of 33 S(p,  ) 34 Cl in inverse kinematics Jennifer Fallis,"— Presentation transcript:

1 CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl Constraining nova observables: Direct measurement of 33 S(p,  ) 34 Cl in inverse kinematics Jennifer Fallis, DRAGON

2 CAWONAPS - Dec 10th, 2010 Motivation Nucleosynthesis calculations of ONe novae predict an overproduction of 33 S by a factor of 150 compared to solar. This could vary by factors of 0.01 to 3 due to the current experimental uncertainty in the rate of 33 S destruction via 33 S(p,  ) 34 Cl.

3 CAWONAPS - Dec 10th, 2010 Motivation

4 CAWONAPS - Dec 10th, 2010 Classification of presolar grains Large over-abundances of several specific isotopes can be used to identify presolar grains, and their astrophysical origins. – 12 C/ 13 C, 14 N/ 15 N, 30 Si/ 28 Si The measured isotopic ratios can constrain models of stellar nucleosynthesis. The mere existence of grains from novae can provide information about nova ejecta. –To get C-rich grains from O-rich ejecta limits condensation conditions

5 CAWONAPS - Dec 10th, 2010 Classification of presolar grains AGB stars and SN nucleosynthesis cannot explain these grain signatures. Seeing an over- abundance of 33 S would be an indicator for ONe novae.

6 CAWONAPS - Dec 10th, 2010 Classification of presolar grains AGB stars J-type C stars SN AGB stars Novae Novae? AGB stars and SN nucleosynthesis cannot explain these grain signatures. Seeing an over- abundance of 33 S would be an indicator for ONe novae.

7 CAWONAPS - Dec 10th, 2010 Classification of presolar grains Sulfides are expected to be incorporated into SiC grains. (K. Lodders and B. Fegley Jr., Meteroritics 30 (1995) 1959) Sulfide measurements are complicated by the H 2 SO 4 used to separate SiC grains. … but a recent paper measured the 34 S/ 32 S ratio in a SiC grain of SNII origin. ( P. Hoppe et al., ApJ 719 (2010) 1370 ) 33 S?

8 CAWONAPS - Dec 10th, 2010 Possible  -telescope target? 33 S(p,  ) 34 Cl is the only means of production of 34m Cl in classical novae. Characteristic  -rays resulting from its subsequent  -decay (t 1/2 = 32 m) might be a future target for  -ray telescopes. –Requires nova ejecta to become transparent to  ’s in a short enough time period, or for there to be large enough amounts of 34m Cl that it hasn’t all decayed in the intervening time. E  = 1.2, 2.1, 3.3 MeV Photo: ESA

9 CAWONAPS - Dec 10th, 2010 Currently, experimental measurements of  only exist down to E r = 434 keV. The energy region corresponding to nova temperatures (0.2-0.4 GK) goes as low as E r = 220 keV. As of 2008, there were two possible states within the Gamow window and 3 just below it, which had not been measured directly. –Deduced from (p,  )  -decay schemes (Waaders, Dassie) –From various indirect studies 34 Cl level structure above 33 S+p F. B. Waaders et al., Nucl. Phys. A411 (1983) 81 D. Dassie et al., Nucl Phys. A276 (1977) 260 & 279 R. M. Del Vacchio et al., Nucl. Phys A265 (1976) 220 H. Nann et al., Phys Rev C. 15 (1977) 1959 C. J. van der Poel et al., Nucl Phys A373 (1982) 81 P. Baumann et al., Phys Rev. C 18 (1978) 247

10 CAWONAPS - Dec 10th, 2010 34 Cl level structure above 33 S+p 1.00E-10 1.00E-09 1.00E-08 1.00E-07 1.00E-06 1.00E-05 1.00E-04 1.00E-03 1.00E-02 1.00E-01 1.00E+00 0.250.30.350.40.45 T (GK) 29 137 172 244 398 434 492 530 620 642 663 710 754 798 434 244 530 398 492 798 754 710 642 663 620 172 137 N A (cm 3 /s/mol) José et al., Astrophys. J. 560 (2001) 897 E r = 244 E r = 398

11 CAWONAPS - Dec 10th, 2010 In 2009: 8 states (6 new!) without any measured  within the relevant energy region. 34 Cl level structure above 33 S+p Recent work by A. Parikh et al. using 34 S( 3 He,t) 34 Cl PRC 80, 015802 (2009)

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13 33 S beam development Stable beams of 33 S from Supernanogan: –1x10 10 pps of 33 S 6+, no contamination seen SUPERNANOGAN

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15 Determining  n recoils = Y = 2 (M beam +m tgt ) (  ). n beam  BGO  CSD  sep  DSSSD 2  m tgt. stopping cross-section / target atom

16 CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl run Re-measured the important 33 S+p resonances at E r = 434 and 492.5 keV. Singles Coincidence E r = 492

17 CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl run Re-measured the important 33 S+p resonances at E r = 434 and 492.5 keV. E r = 492

18 CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl run Re-measured the important 33 S+p resonances at E r = 434 and 492.5 keV. Er = 492.5 keV –3240 counts seen in ~ 3hrs –  (preliminary) : 0.07(1) eV –  (Endt90) :0.088(25) eV Er = 434 keV –2912 counts seen in ~ 3 hrs –  (preliminary) : 0.06(1) eV –  (Endt90) :0.050(13) eV P. M. Endt, Nucl. Phys. A521 (1990) 1 So far so good...

19 CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl run E r = 400, 342, 281, 244 and 183 keV –To be astrophysically relevant needed on the order of 330, 50, 8, 3 and 0.5 counts/hr respectively –No coincidence events above background seen 244 183214 400 ~10 hrs~18 hrs ~38 hrs ~21 hrs

20 CAWONAPS - Dec 10th, 2010 33 S(p,  ) 34 Cl run E r = 310 keV: 10 events in 17 hrs Er = 293 keV: 31 events in 13.5 hrs 293 310

21 CAWONAPS - Dec 10th, 2010 Resonance Strength (  )

22 CAWONAPS - Dec 10th, 2010 Energy Measurement & Determining E r ISAC beam energy is measured at DRAGON charge slits –without gas : to determine E beam –with gas : to measure stopping power

23 CAWONAPS - Dec 10th, 2010 Energy Measurement & Determining E r ISAC beam energy is measured at DRAGON charge slits –without gas : to determine E beam –with gas : to measure stopping power Location of narrow resonances in gas target can be determined using BGO array –knowing the target profile, location in target and stopping power, we can determine E r

24 CAWONAPS - Dec 10th, 2010 BGO z-position E r =492 keV 431 293 310

25 CAWONAPS - Dec 10th, 2010 Conclusions With little contribution to the rate from the previously unmeasured states, the lower limit shown above, based on existing measurement, is likely to remain the current experimental rate of the 33 S(p,  ) 34 Cl reaction. Image from A. Parikh et al., PRC 80, 015802 (2009) Preliminary!

26 CAWONAPS - Dec 10th, 2010 Collaborators A. Parikh (Technische Universität München) C. Ruiz, D. A. Hutcheon, L. Buchmann, U. Hager, D. Ottewell, S. Sjue (TRIUMF) B. Davids, S. Reeve (TRIUMF/Simon Fraser University) J. M. D’Auria (Simon Fraser University) S. Bishop, C. Herlitzius (Technische Universität München) C. Wrede (U Washington) C. M. Deibel (JINA/ Argonne), J. A. Clark (Argonne) A. A. Chen (Excellence Cluster Universe, McMaster), K. Setoodehnia (McMaster) U. Greife (CSM), A. M. Laird (York), P. D. Parker (Yale), C. Vockenhuber (ETH Zurich), J. José (UPC, IEEC Barcelona) B. Guo, G. Lian, Y. Wang, Z. Li, E. Li, W. Liu (China Institute of Atomic Energy)

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