Download - Down and Up Along the Proton Dripline
![Page 1: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/1.jpg)
Down and Up Along the Proton Dripline
Heavy One-Proton Emitter
Light One-Proton Emitter
Light Two-Proton Emitter
Heavy Two Proton Emitter
![Page 2: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/2.jpg)
Proton Radioactivity
-60
-40
-20
0
20
40 Centrifugal (l=5)
Coulomb
Nuclear
Radius (fm)
V (
MeV
)
20 40
![Page 3: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/3.jpg)
Strong Influence on Angular Momentum
V (
MeV
)
l=0
l=5
T1/2(l=0) = 3s
T1/2(l=5) = 81ms
E=1.25 MeV
Radius (fm)
-40
-20
0
20
20 40 8060
Lu15171 80
![Page 4: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/4.jpg)
Heavy Proton Emitter
Long lifetimes due to Coulomb and angular momentum barrier Produce in fusion evaporation reactions or fragmentation Separate and subsequently stop in a detector for identification Use segmented silicon strip detectors for a delayed decay
![Page 5: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/5.jpg)
1p Separation Energies (Odd p-numbers)
T. Radon et al., Pramana 53 (1999) 69
![Page 6: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/6.jpg)
1p Separation Energies (Even p-numbers)
T. Radon et al., Pramana 53 (1999) 69
![Page 7: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/7.jpg)
Structure and Deformed Emitters
C. J. Gross et al. 113Cs
A. A. Sonzogni et al. 131Eu, 141Ho, 145Tm
J. Uusitalo et al. 155Ta
K. Rykaczewski et al. 140Ho, 141Ho
T. N. Ginter et al. 150Lu
K. S. Toth et al. 151Lu
P. J. Woods and C. N. Davids, Annu. Rev. Nucl. Part. Sci. 47 (1997) 541
![Page 8: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/8.jpg)
Q-Values and Branching Ratios
R. J. Irvine et al., Phys. Rev. C 55 (1997) R1621
C. N. Davids et al., Phys. Rev. C 55, (1997) 2255
161Re167Ir
![Page 9: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/9.jpg)
Where is the Proton Dripline?
![Page 10: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/10.jpg)
“Short”-Lived Proton Emitters
C.R. Bingham et al.
![Page 11: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/11.jpg)
100Sn
K. Sümmerer et al., Nucl. Phys. A616 (1997) 341c
![Page 12: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/12.jpg)
rp - Process
5352515049
525150
5049484746
CoFe45
8079
8382
Zr
Nb
Mo
81
8483
M. F. Mohar et al., Phys. Rev. Lett. 66 (1991) 1571
B. Blank et al., Phys. Rev. Lett. 77 (1996) 2893
B. Blank, J. Phys. G 24 (1998) 1385
![Page 13: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/13.jpg)
New Isotopes Along the Dripline
B. Blank, J. Phys. G 24 (1998) 1385B. Blank et al., Phys. Rev. Lett. 77 (1996) 2893
![Page 14: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/14.jpg)
Prompt Decay from a Well-Deformed Band
p
D. Rudolph et al., Phys. Rev. Lett. 80 (1998) 3018
![Page 15: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/15.jpg)
First Proton Radioactivity
7/2-
3.04
0
19/2-
247 ms
0
3.19
(7/2-)
12
10
8
6
4
2
0
Ene
rgy
(MeV
)
0.840 0+
2+(19/2-)
+
26Fe2753
26Fe2652
27Co2653
1.5%
Joseph Cerny and J. C. Hardy, Annu. Rev. Nucl. Part. Sci. 27 (1977) 333
![Page 16: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/16.jpg)
-Delayed Proton Emitters
S. Czajkowski et al., Nucl. Phys. A628 (1998) 537
![Page 17: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/17.jpg)
Light Proton Emitter
(Very) short lifetimes due to small Coulomb and no or very small angular momentum barrier (l=0,1,2)
Produce in transfer reactions or fragmentation Identify by complete kinematic reconstruction in flight
![Page 18: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/18.jpg)
151Lu and 12O
![Page 19: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/19.jpg)
Definition of Radioactivity
Joseph Cerny and J. C. Hardy, Annu. Rev. Nucl. Part. Sci. 27 (1977) 333
“…should lead to lifetimes longer than 10-12 sec, a possible lower limit for the process to be called radioactivity.”
“…should lead to lifetimes longer than 10-12 sec, a possible lower limit for the process to be called radioactivity.”
![Page 20: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/20.jpg)
Search for Di-Proton Emitters
Predicted by Goldansky in 1960 Until recently (?) elusive In-Flight Decay (Short lifetimes)
Ground State Excited States
Resonance Scattering Coulomb Excitation Neutron-Stripping
Implantation/Decay (Long lifetimes) Beta-Delayed Emitters Ground-State Emitters
![Page 21: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/21.jpg)
Potential Two Proton Emitter
![Page 22: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/22.jpg)
Definitions
Di-Proton Decay Sequential Decay
12O
11N+p
10C+p+p
12O
10C+2p
10C+p+p
12O 10C+2p11N+p 12O 10C+2p11N+p
Simultaneous Decay
12O
10C+p+p
12O 10C+2p11N+p
![Page 23: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/23.jpg)
Three Body Model
L. V. Grigorenko et al., Phys. Rev. Lett. 85 (2000) 22
![Page 24: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/24.jpg)
Three-Body Decay Paths
L. V. Grigorenko et al., Phys. Rev. Lett. 85 (2000) 22
![Page 25: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/25.jpg)
Light Two-Proton Emitters
![Page 26: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/26.jpg)
Two-Proton Decay of 6Be
g.s.
1.67
0.59
-1.374He+2p
5Li+p6Be
(0+)(3/2-)
(2+)
D.F. Geesaman et al., Phys. Rev. C15 (1977) 1835
![Page 27: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/27.jpg)
Transfer Reactions with Radioactive Beams
O13O13 O12
O12
Be9 Be10
TelescopeC10
p Light ChargedParticle Arrayp
![Page 28: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/28.jpg)
Production and Identification of short-lived Nuclei
![Page 29: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/29.jpg)
Decay Energy Spectrum of 12O
= 575 keVEDecay = 1.77 MeV
![Page 30: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/30.jpg)
Two-Proton Angular Distribution
Di-Proton
Sequential
![Page 31: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/31.jpg)
Decay Width
Sequential Decay
12O
11N+p
10C+p+p
12O 10C+2p11N+pHowever:
Γcalc 10 keV
Γmeasured = 575 keV
![Page 32: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/32.jpg)
Elastic Resonance Scattering
L. Axelsson et al., Phys. Rev. C 54 (1996) R1511
![Page 33: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/33.jpg)
Ground State of 11N
A. Azhari, et al. Phys. Rev. C57, 628 (1998)
J. M. Oliviera, et al. Phys. Rev. Lett. 84, 628 (2000)
K. Markenroth, et al. Phys. Rev. C62, 034308 (1998)
1.45 MeV
1.63 MeV1.27 MeV11N
![Page 34: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/34.jpg)
Two Proton Decay of 12O
Old
New
??2.0 MeV1.8 MeV
1.8 MeV ~1.5 MeV
12O 11N+p 10C+2p
![Page 35: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/35.jpg)
Di-Proton Decay of 16Ne?
L. V. Grigorenko et al., Phys. Rev. Lett. 88 (2002) 042502
![Page 36: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/36.jpg)
New Shell Structure?
Z=8
N=8
N=16 ?
N=20
??
![Page 37: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/37.jpg)
Vanishing of the Proton Z=8 Shell ?
11N (-1.92MeV)
7B – 11N – 15F
5Li – 9B – 13N – 17F
Z=8
![Page 38: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/38.jpg)
Vanishing of the Proton Z=8 Shell ?
11N (-1.27MeV)15F ??
![Page 39: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/39.jpg)
Mass of 15F ??
11N 15F ??
![Page 40: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/40.jpg)
Previous 15F Measurement
G. J. KeKelis et al., Phys. Rev. C 17, 1929 (1978)
Binding Energy
of 15F : –1.47 MeV
= 1 MeV
![Page 41: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/41.jpg)
Theoretical Prediction
S. Grevy, O. Sorlin, and N. Vinh Mau, Phys. Rev. C56 (1997) 2885
![Page 42: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/42.jpg)
Invariant Mass Measurements at GANIL
2%
87%
11%
Primary Beam: 24Mg Secondary Beams:
20Mg, 18Ne, 17F Fragments Energies:
35-43 MeV/nucleon Stripping Reactions Detectors:
SPEG SpectrometerMUST array
![Page 43: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/43.jpg)
15F 14O + p
T. Zerguerras et al., to be published
Relative to KeKelis et al.
Binding Energy of 15F : Egs = –1.00 0.08MeV
= 1.23 0.22MeV
![Page 44: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/44.jpg)
Mass of 15F !!
11N 15F !!
![Page 45: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/45.jpg)
Two Proton Decay of 16Ne
Old
New
1.5 MeV1.4 MeV
1.4 MeV 1.0 MeV
??
16Ne 15F+p 14O+2p
15F
![Page 46: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/46.jpg)
Two Proton Decay of 19Mg ??
Masses of 19Mg and 18Na are not known
Stripping reactions:20Mg 18Na 17Ne + p20Mg 19Mg 17Ne + 2p
~1.8 MeV
~1.2 MeV ??
19Mg 18Na+p 17F+2p
Theoretical Predictions
![Page 47: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/47.jpg)
First Measurement of the Mass of 18Na
No events observed for 20Mg 19Mg 18Na + 2p
Binding Energy of 18Na : Egs = –0.411 0.05 MeV
= 0.34 0.09 MeV
![Page 48: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/48.jpg)
Decay of 19Mg Sequential ??
~1.2 MeV
19Mg 18Na+p 17F+2p
0.41 MeV
Two-Proton Decay will most likely be sequential..
.. unless the mass of 19Mg is also underpredicted
Measure the mass of 19Mg
![Page 49: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/49.jpg)
Intermediate (1p) Nuclei
![Page 50: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/50.jpg)
Two-Proton Decay of 14O*
2HeSequential
12C+2p
13N+p
14O
6.57
0
4.63
2.37
3.517.77
6.59
5.17
9.72
1/2+
3/2+
2+
0+
0+
C.R. Bain et al., Phys. Lett. B373 (1996) 35
![Page 51: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/51.jpg)
Level and Decay Scheme of 17Ne
![Page 52: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/52.jpg)
-Decay of the First Excited State
M. J. Chromik et al., Phys. Rev. C55 (1997) 1676
![Page 53: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/53.jpg)
Experimental Setup
![Page 54: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/54.jpg)
Decay Energy Spectrum of 17Ne
Cou
nts
![Page 55: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/55.jpg)
Experimental Setup
17Ne
Position sensitivedetectors
15O p
Target
40x40 Silicon strip detector: Low gain: ==> 15O position High Gain: ==> proton position
2x2 Silicon quadrant detector: 15O energy loss
2x2 Silicon quadrant detector: 15O energy
48 element CsI detector proton energy
40x40 Silicon strip detector proton position energy
2x2 Silicon quadrant detector: proton energy loss
![Page 56: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/56.jpg)
Breakup Reactions in the Detectors can be identified using the new Setup
15O,2p17Ne
15O,2p17Ne
Reaction in the Target
Breakup in the First Pin
E in Pin1 [MeV]
17Ne Penetrating the first Pin
Breakup Pos. [m]
![Page 57: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/57.jpg)
Coulomb Excitation of 17Ne
Decay Energy [keV]
Nu
mb
er
of C
oun
ts
M. Chromik et al, to be published
![Page 58: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/58.jpg)
18Ne 17Ne* 15O + 2p
No evidence for 2p decay from
the first excited state in 17Ne
![Page 59: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/59.jpg)
Two-Proton Decay of 18Ne?
J. Gomez del Campo et al., Phys. Rev. Lett. 86 (2001) 43
![Page 60: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/60.jpg)
One and Two Proton Decay
1p= 50 keV
2p= 21-57 eVJ. Gomez del Campo et al., Phys. Rev. Lett. 86 (2001) 43
![Page 61: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/61.jpg)
Correlated or Uncorrelated?
Relative Energy Opening Angle
J. Gomez del Campo et al., Phys. Rev. Lett. 86 (2001) 43
![Page 62: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/62.jpg)
2p and 3p Decay of 31Ar
31Cl
31Ar18.55
12.34
-decay
7.45
4.706.10
30S+p
29P+2p
28Si+3p
IAS
2p
3p
D. Bazin et al., Phys. Rev. C45 (1992) 69
I. Mukha et al., Nucl. Phys. A630 (1998) 394c
![Page 63: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/63.jpg)
Two-Proton Radioactivity
W. E. Ormand, Phys. Rev. C53 (1996) 2145
W. E. Ormand, Phys. Rev. C55 (1997) 2407
B. A. Brown, Phys. Rev. C43 (1991) R1513
38Ti (0.4-2.3)x10-12 ms 39Ti 0.4-2000 ms 45Fe 10-5-10-1 ms 48Ni 0.01-3660 ms 63Se 0.3-5000 ms
![Page 64: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/64.jpg)
Decay Width and Lifetime Predictions
L. V. Grigorenko et al., Phys. Rev. Lett. 85 (2000) 22
![Page 65: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/65.jpg)
45Fe: 2-Proton Decay at GSI
M. Pfützner et al., to be published
![Page 66: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/66.jpg)
45Fe: 2-Proton Decay at GANIL
J. Giovinazzo et al., to be published
![Page 67: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/67.jpg)
45Fe: Di-Proton or Sequential?
G. Audi and A.H. Wapstra,
Nucl. Phys. A595 (1995) 409
![Page 68: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/68.jpg)
Bridging the Waiting Points
H. Schatz et al., Phys. Rep. 294 (1998) 167
![Page 69: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/69.jpg)
Two-proton emitters and the (2p,) rates
http://csep10.phys.utk.edu/astr162/lect/index.html
![Page 70: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/70.jpg)
17Ne ( ,2p) 15O
15O+2p 16F+p 17Ne
p
p
p
![Page 71: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/71.jpg)
15O(2p,)17Ne
15O+2p 16F+p 17Ne
p
p
p
Q
-QzQz+1
![Page 72: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/72.jpg)
Does the (2p,) compete with the ()
4
8
12
16
20
0.2 0.4 0.6 0.8 1
-45
-40
-35
-30
-25
-20
-15
-10
-5
0.1 1
Total Reaction Rate
T (GK) T (GK)
Den
sity
[g /
cm3 ]
Lines of equal rates:
p
p
![Page 73: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/73.jpg)
20Ne(3He,6He)17Ne
V. Guimarães et al. Phys. Rev. C58 (1998) 116
![Page 74: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/74.jpg)
New Level Scheme for 17Ne
V. Guimarães et al. Phys. Rev. C58 (1998) 116
5/2_
5/2_1/2+
1/2+
![Page 75: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/75.jpg)
Modified Reactions Rates for 16F(p,)
Total Reaction Rate
-45
-40
-35
-30
-25
-20
-15
-10
-5
0.1 1
T (GK)
![Page 76: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/76.jpg)
Does the (2p,) compete with the () now?
4
8
12
16
20
0.2 0.4 0.6 0.8 1
T (GK)
Den
sity
[g /
cm3 ]Lines of equal rates:
p
p
![Page 77: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/77.jpg)
Use (,2p) to study (2p,)
Final nucleus following (2p,) is particle stable Use Coulomb dissociation (,2p) on stable nucleus Potential waiting point candidates:
15O(2p,)17Ne 18Ne(2p,)20Mg 38Ca(2p,)40Ti
64Ge(2p,)66Se 68Se(2p,)70Kr 72Kr(2p,)74Y
J. Görres, M. Wiescher, F.-K. Thielemann, Phys. Rev. C51, 392 (1995)
F. Käppeler, F.-K. Thielemann, and M. Wiescher,Ann. Rev. Nucl. Part. Sci. 48, 175 (1998)
![Page 78: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/78.jpg)
68Se(2p,)70Kr
68Se+2p 69Br+p 70Kr
p
p
p
High T (>2GK) : total = (Z) + f(T)*exp(Q)*(Z+2)
Q
-QzQz+1
Low T (<2GK) : total = (Z) + g(T)*exp(-Qz)*p
![Page 79: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/79.jpg)
Reduction of Stellar Lifetime
H. Schatz et al., Phys. Rep. 294 (1998) 167
![Page 80: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/80.jpg)
Energies and decay properties of the Z(waiting point +2) nucleus:
Coulomb excitation: () and (,2p)
70Kr(,2p)68Se
Mass of the unstable Z(waiting point +1) nucleus:
Transfer reaction:
9Be(70Br,69Br)
68Se + p
What is needed?
![Page 81: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/81.jpg)
Beam Intensities
70Kr(,2p)68Se 70Br
70Kr
68Se 9Be(70Br,69Br)
RIA: 8x107/s 70BrRIA: 4x104/s 70Kr
CC : 7x105/s 70BrCC : 3x102/s 70Kr
![Page 82: Down and Up Along the Proton Dripline](https://reader036.vdocuments.us/reader036/viewer/2022062422/56813877550346895da025bf/html5/thumbnails/82.jpg)
Conclusions
Still no conclusive evidence for di-proton decay Light nuclei:
“Phase space wins”: If it can decay sequential, it will Ground-state di-proton decay very unlikely Lower ground-state energies measured for 11N, 15F and 18Na Still unresolved problem of large width in 12O Measure 19Mg !!
Heavier nuclei: First evidence for two-proton decay in 45Fe Determine the proton correlations Measure the mass of 44Mn Deformation, structure and mass measurements