Fixed, e768s, Sat Jul 20 12:06:00 2019, Christian, OTHER, General, , Previous Papers - gamma decays from states in the 4-MeV region 
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| Further to the previous post on gamma-ray lines, attached is Kanungo's paper on doppler-attenuation measurement of the 4033 line for lifetime measurement. The lower-energy lines are, however, not included in the figures. |
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Fixed, e768s, Sat Jul 20 12:57:41 2019, Christian, OTHER, General, , Previous Papers - gamma decays from states in the 4-MeV region
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2019 paper by Hall, Bardayan, et al., gamma decays of 4.14 and 4.20 states, g-g-t triple coincidences.
Abstract:
The 15O(α,γ)19Ne reaction is responsible for breakout from the hot CNO cycle in Type I x-ray bursts. Understanding the properties of resonances between Ex = 4 and 5 MeV in 19Ne is crucial in the calculation of this reaction rate. The spins and parities of these states are well known, with the exception of the 4.14- and 4.20-MeV states, which have adopted spin-parities of 9/2− and 7/2−, re- spectively. Gamma-ray transitions from these states were studied using triton-γ-γ coincidences from the 19F(3He,tγ)19Ne reaction measured with GODDESS (Gammasphere ORRUBA Dual Detectors for Experimental Structure Studies) at Argonne National Laboratory. The observed transitions from the 4.14- and 4.20-MeV states provide strong evidence that the Jπ values are actually 7/2− and 9/2−, respectively. These assignments are consistent with the values in the 19F mirror nucleus and in contrast to previously accepted assignments.
Noteworthy is that they also don't observe the 3.96MeV transition from the 4.20MeV state, consistent with our observations.
No data is given on the 4.033 MeV state [potentially see further discussion in the corresponding PhD thesis].
From the data, however, it would seem that the (3He,t) reaction does not really populate the 4033 state [otherwise, the 4033 transition should have been seen in Figure 4]. |
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Fixed, e768s, Sun Jul 21 17:57:08 2019, Christian, OTHER, General, , Previous Papers - gamma decays from states in the 4-MeV region
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In comment to previous entry (see thread), on the 2019 Hall paper on 19Ne transitions:
Note that Fig 4.c is described as: Gated on the 238-keV 5/2+ to ground-state transition. The 3897.5-keV transition from the 4141.8-keV state is observed for the first time. This means the spectrum is designed such that it wold not show the 4033 transition. Therefore, whether they are sensitive to this is an open question. See also PhD thesis of Hall for further details? |
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Fixed, e768s, Mon Jul 22 10:10:02 2019, Christian, OTHER, General, , Previous Papers - alpha-branching ratios for states in the 4-MeV region
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Branching ratio data overview from Tan et al. (PRL 2007, attached):
Ex/MeV B_alpha
4.03 2.9(21)e-4
4.14/4.20 1.2(5)e-3
4.38 1.2(3)e-3
4.55 0.07(2)
In the spectra so far, we are very clearly seeing the 4.14/4.20 MeV doublet. We may also be seeing some indication of the 4.38, 4.55 and/or 4.60 MeV states above 4 MeV (4.14, 4.27, and 4.36 MeV respectively, as dominant lines). Note that we have no alpha-branching-ratio data for the 4.60MeV state, and that most likely the gamma-ray events we currently see above 4MeV are the 4.14MeV and 4.36MeV lines (4.38 and 4.60 MeV states).
Comments to lifetimes from Mythili et al., (PRC 2008, attached). The relevant lifetimes are for the states between 4.14 and 4.55. Only dominant errors are given, for details, see attached table:
Pre-2008 Mythili
Ex/MeV lifetime/fs lifetime/fs
4.14 18(+2/-3) 14(4)
4.20 43(+12/-9) 38(+20/-10)
4.38 5(+3/-2) <5.4 (95% CL)
4.55 15(+11/-5) 19(4)
In combination:
4.38 MeV: Branching ratio is fairly well known. Lifetime is very poorly known, if at all. We have 7 counts so far (provisional), in the 4.14 MeV peak after about 3 days of beam on target.
4.55 MeV: Branching ratio is fairly well known. Lifetime is fairly well known, but it is not clear that we see this decay.
4.14/4.20: Lifetimes is known reasonably well for 4.14, poorly for 4.20, and differ by about a factor of 2-4 (within error). Branching ratio is only known in combination between the two. This complicates normalisation to these two states greatly, as we would in principle have to assume any combination of this contribution from 4.14, 4.20, or combined. In their paper (Tan 2007), they do state for this measurement that: "The measured􏰑 peak [in the alpha-spectrum] seems to be lower in energy than the simulated one, indicating that these decay events are more likely from the 4.14-MeV state.". Looking at the spectrum they refer to, however, I would not say that this is in any way a clear cut argument (and they do state it with some hesitation).
In summary: because of the overlap of the 4.14 and 4.20 states in the branching ratio data [which I should admit that I had missed when investigating the previous data and results earlier] it will be much harder than expected to cross check normalisation of the data based on the observed lifetimes and alpha branching ratios for 19Ne resonances.
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Fixed, e768s, Thu Jul 25 11:05:18 2019, Francois de Oliveira, OTHER, General, , Previous Papers - alpha-branching ratios for states in the 4-MeV region
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| In the reaction 15N(7Li,t)19F, the ratio between the measured cross sections is R(3/2+/9/2-)>29. We should get the same ratio in 19Ne. In 19Ne, the 3/2+ state decays with Eg=4033 keV (80%), the second with 2632 keV (100%), gamma efficiency = 4% and 5.5%, this gives a ratio between the number of counts measured in the 2632 keV and in the 4033 keV > 29 x 100/80 x 5.5 / 4 ~ 50. |
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Fixed, e768s, Thu Jul 18 22:10:58 2019, Jenn, OTHER, General, , Previous Papers
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Fixed, e793s, Sat Mar 13 19:54:47 2021, Louis, Sarah, OFFLINE, General, CD2, Preliminary spectroscopic factors
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1) Preliminary spectroscopic factors has been extracted for the first 2- exited state @ 143 keV and for the 0- excited state @ 1985 keV. DWBA calul has been performed by cyril for a p3/2 transfer at 0MeV and a p1/2 transfer at 2MeV. Experimental differential cross section has been extracted by normalising the number of counts with the total number of incoming 47K (from CATS div), the number of deuteron in the target, and correcting from MUGAST geometrical efficiency (computed by franco for the gs) and from AGATA efficiency (with the energy depence given by Emmanuel). The 1p3/2 C2S of the first 2- state was found to be 0.22. The 1p1/2 C2S of the 0- excited state was found to be 0.88.
2) gg analysis from Chloé identified a new transition at 997keV in coincidence with the 143 keV gamma. Ex spectra gatted on the 997 keV transition is shown. One can identified a clear state at about 1.1MeV corresponding to the 998+143 gamma cascade. A second clear state is identified at 2.2 MeV but no 1.2MeV gamma has been identified to complete the gamma cascade of this state.
3) the usual analysis plots updated with full statistics. |
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Fixed, e744s, Sun Apr 14 23:41:32 2019, Valerian, Simon and Belen, OFFLINE, Software, CH2, Preliminary results for 2p
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| Preliminary results using runs 122 : O 1 2 3 4 |
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Fixed, e775s, Sun Mar 1 17:04:43 2020, Marlène François, RUN, General, , Preliminary analysis of runs from 128 up to now (169) 6x
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| Preliminary analysis with all stat up to now. |
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Fixed, e744s, Tue Apr 16 21:48:31 2019, Valerian, Belen, Sylvain, Iulian, Simon and Blaise-Mael, OFFLINE, Software, CH2, Preliminary Dalitz plot
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Fixed, e744s, Mon Apr 8 00:41:53 2019, Francois, OTHER, General, , Predictions for VAMOS plots with 14N and 14O beams
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Fixed, e768s, Fri Jul 19 15:18:38 2019, Diego Ramos, OFFLINE, General, LiF, Position of 19Ne in dE:E in VAMOS
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| Conclusion: IC pressure not needed to be reduced. |
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Fixed, e793s, Thu Mar 11 21:14:26 2021, Fairouz & Franco, OFFLINE, General, CD2, Plots run 51-56
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Top left: kinematic plot with the main levels observed. The orange lines are (d,p), (d,t), (d,d) and (12C,12C) reactions by 47Ti. The yellow line is 47K(p,p), the green line 47K(d,d).
Top right: in black Ex spectrum with gate on VAMOS, in red with also the gate on a gamma and scaled by a factor 3 for better comparison.
Bottom left: Egamma vs Ex with gate on VAMOS.
Bottom right: Egamma with gate on VAMOS. |
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Fixed, e775s, Thu Mar 5 17:07:40 2020, Freddy, Adrien, OTHER, General, N/A, Pedestals: summary for E775s 16x
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Two runs are useful for pedestals after experiment:
run 190 --> normalized pedestals (nominally to 8192)
run 191 --> raw pedestals
The pedestal values read from DAS on the 18th of February were in principle loaded in GECO at the beginning of the experiment and are attached:
ped_MUVIX_sectorX.dat
The pedestals read from GECO at the end of the experiments (so used during the experiment) are also attached and are those named:
MUVIX_sectorX.txt
It would be good to check they are consistent with run 191. |
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Fixed, e768s, Mon Jul 22 11:21:25 2019, mugast, MUST2, Software, , Pedestals of MG3
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Pedestals of MG3_X have changed yesterday, they are back to about 8200 as they should be --> saved in ped_muvi2sec2_22072019_new
We are using wrong pedestals (of about 9600) --> the pedestals are saved under mugast account as ped_muvi2_sec2_22072019_sameas_1807219
We kept the same pedestals but we reduced the pedestal suppression to 0 - 6800 in order not to suppress the data of one other 2 mates.
The attached spectrum shows that all the X of MG3 are recovered (although the impact matrix still does not work) |
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Fixed, e793s, Fri Mar 5 16:16:28 2021, mugast, DAQ, Software, , Pedestals for E793S 12x
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Pedestal alignment was performed for Energy qnd Time for all cards with cooling at 0°.
The values are attached here and saved in : cd ganacq_manip/mugast/das-save/pedestal-save/pedestal_5march2021_15h54/ |
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Fixed, e744s, Mon Apr 8 11:58:37 2019, Valerian, OTHER, General, N/A, Particle identification with CATS or HF 6x
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After discussing about using the HF, I join as a reference what was obtained during experiment e744 of last year. We can see that using an external TAC the time resolution is much worse using HF.
I also join as a reference the same timing using MUVI.
Edit: Added simulation with 3 different time resolution.
Joined plot are :
- TAC MUST2-CATS
- TAC MUST2-HF
- Calibrated ToF on MUVI
- Simulated : CATS (500ps resolution)
- Simulated : HF best case scenario (2ns)
- Simulated : HF as in previous experiment (4ns)
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Fixed, e775s, Tue Feb 25 11:50:16 2020, Marlène & Franco, OFFLINE, General, , PID with gate on T_FPMW_HF
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| The black points are what remains after putting the condition abs(T_FPMW_HF-13000)<1000, for MG1 and the annular. |
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Fixed, com2019, Tue Apr 2 08:52:16 2019, Freddy, MUST2, General, 3-alpha, PEDESTAL save - run 165
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Normalized Pedestal value loaded in DAS for run 165 (3-alpha)
folder: /home/mugast/ganacq_manip/mugast/das-save/pedestal-save/run165
NB: Not sure when this pedestal values were read from the board, in principle should have been read just before the run. |
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Fixed, e744s, Sat Apr 13 14:28:00 2019, Marion, Kseniia, Dieter, Didier, Guiseppe, IuliaH, BEAM, General, CH2, PCP information - beam interruption
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beam interrupted to an octupole (?) failure - prevision to be back after 10-15 min (PCB info)
14:35 h beam is back |
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