CERN. Geneva. ISOLDE and Neutron Time-of-Flight Experiments Committee

INTC

INTC-002

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CERN/ISTC 99-8ISTC 210 December 1999ISOLDE AND NEUTRON TIME-OF-FLIGHTEXPERIMENTS COMMITTEE (ISTC)Minutes of the second meeting onMonday 29 November, 1999CLOSED    SESSION    Present:  B. Allardyce, J. Aystö, C. Détraz, J.-P. Duraud, J. Eades (Secretary), H. Flocard(Chairman), K.L. Kratz, K.P. Lieb, L. Maiani, E. Migneco, T. Nilsson,H. Ravn, C. Rossi-Alvares, B. Rubio, W. Scobel, G. Sletten, P. van Isacker,R. Voss, P. Walker.Apology:  W. David.At its September meeting, the Committee decided that a substantial part of the present meetingwould be devoted to an examination of the backlog of approximately 700 shifts in the ISOLDEexperimental programme. In the meantime three new ISOLDE proposals have been received. Noneof these has special scheduling constraints, and their possible addition to the ISOLDE schedule canbe adequately taken into account pending the Committee's later decision. It was therefore decidedto defer the Open presentation of these proposals until the February meeting, cancel the OpenSession of the present meeting, and replace it by an extended Closed Session exclusively devotedto the backlog problem.The minutes of the September meeting were approved after noting that the 3.9 x 1013 protons perpulse mentioned therein in connection with a possible change of the PS booster energy to 1.4 GeVshould not be considered as an operational level, although such an intensity has in fact beenachieved in test situations.The CERN Director General, L. Maiani opened the proceedings by noting that the Research Boardhad received the Chairman's remarks concerning the present review of the backlogged experimentswith satisfaction, and encourages the ISTC in its timely confrontation of this problem.Thomas Nilsson, ISOLDE coordinator then presented a breakdown of the shift backlog. Hereported that one year ago there were 621 outstanding shifts of which 196 were on the account ofREX-ISOLDE. In the last four meetings, a further 257 shifts have been approved,  while 195 weredelivered during the 1999 run period. The present situation is that there are 692 outstanding shifts,208 of which are due to REX-ISOLDE. The reasons for this accumulation vary,  from lack ofresources to the desire of some experimental groups to spread their experiments over several years.In discussing this report, H. Flocard stressed that the aim of the present meeting was not ascientific re-evaluation of the experiments concerned. This job had been done at preceding ISCCommittee meetings with the same qualifications and competence as the present ISTC and thedecisions taken had subsequently been approved by the Research Board. The task before the ISTCis rather to decide on a global strategy for reducing the backlog to what is considered by theISOLDE coordinator to be a normal working value, corresponding to about 1.5 years of runningtime (i.e. a reduction by about 150 shifts).. 22C. Détraz, CERN Research Director, pointed out that an additional reason for carrying out thepresent review is to explain to the wider community of CERN why unfinished experimentsapproved several years ago were still scientifically valid. A failure to do this might be seen as astructural weakness in the ISOLDE resarch programme. In this view, periodic assessments ofprogress of approved experiments should play an important role in the Committee's future attemptsto keep the backlog down to a reasonable value.Experiments contributing to the backlog that, according to a study of the programme made by thechairman with the help of the ISOLDE coordinator, appear to be worth a closer look by theCommittee were then briefly discussed under four categorisations suggested by the chairman. Allexperiments in the same category were considered to be on an equal footing.I.    Experiments   recommended    by   the     Committee    before    1996   (but    excluding     REX-ISOLDE):  IS300 (ISC 91-4/P2): A search for axions and massive neutrons.IS301 (ISC 91-6/P4): Effect of particle-core-vibration coupling near the double closed 132Snnucleus from precise magnetic moment measurements.IS306 (ISC 91-3/P1, ISC 91-24 P1 Add.1): Systematic measurements of the Bohr-Weisskopfeffect at ISOLDE.IS311 (ISC 91-30/P18): The electronic structure of impurities in semiconductors.IS314 (ISC 91-34/P 22): Measurements of electric quadrupole moments of neutrondeficient Au, Pt, and Ir nuclei with NMR-ON in  hcp-Co.IS315 (ISC 91-7/P5, ISC 92-6/P5 Add.1, ISC 95-20/P5 Add.2): COllinear SpectroscopyMeasurements using a Pulsed Laser Ion Source (COMPLIS).IS332 (ISC 93-5/P43): The Search for M3 transitions in 183Pt and 181Os.IS347 (ISC 94-25/P68): Radioactive beam EXperiments at ISOLDE: Coulomb excitation andneutron transfer reactions of exotic nuclei.These experiments were initially allocated a total of 176 shifts, of which 88 are still to be used. Itwas decided to withhold the outstanding shifts for these experiments until discussions betweenexperimental spokesmen and Committee members appointed as referees on an experiment-by-experiment basis have clarified their present status. A letter will inform each spokesman about therelevant Committee members and the information requested.II.    Experiments   recommended    between    1996    and    1998    and    having    used   less   than     80%     of    theirallocated    beam   time:  IS302 (ISC 91-9/P6, ISC 95-8/P6 Add.1): High-accuracy mass determination of unstable nucleiwith a penning trap mass spectrometer.IS303 (ISC 91-11/P8): Tilted-foil polarisation and magnetic moments of mirror nuclei atISOLDE.(ISC 96-31/P87): Measurement of the magnetic moments of T=3/2 Nuclei in the S-D shell usingthe tilted foil polarization technique.IS344 (ISC 94-7/P60, ISC 96-12/P60 Add.1):  Laser spectroscopy of neutron rich bismuthisotopes.IS355 (ISC 96-2/P77): Search for detour transitions in the radiative IC decay of 81Kr.. 33IS356 (ISC 96-11/P80): Search for physics beyond the standard model via positron polarizationmeasurements with polarized 17F.IS357 (ISC 96-15/P81, ISC 96-26/P81 Add. 1): Gold and platinum in silicon-isolated impuritiesand impurity complexes.IS362 (ISC 97-12/P89): Diffusion in intrinsic and highly doped III-V Semiconductors.IS365 (ISC 97-31/P96): Nuclear spectroscopy with copper isotopes of extreme N/Z ratios.The initial allocation totalled 276 shifts, of which 119 remain. In these cases, the shift allocationstands, but spokesmen will again be asked by letter to provide information to the Committeeconcerning present status, plans etc. As above, Committee members will be appointed to everyexperiment, and spokesmen are strongly advised to discuss their case with these referees.III.    Test    experiments    and    LOIs   reccommended    1996-1998   (18    shifts    allocated,    15    used):  ISC 96-23/P83: Test: Electron Paramagnetic Resonance Investigations of Isolated Impurities andImpurity Pairs in Silicon.ISC 95-30/I18: Test:  73Ge Moessbauer spectroscopy in semiconductors.ISC 97-28/P95: Test: Study of 163Ho-decay for a neutrino mass experiment.The procedure for test experiments and LOIs will be identical to that for category 2.IV.     REX-ISOLDE:  Some 150 shifts were initially allocated to the REX-ISOLDE source-accelerator project in 1995,while about 60 more have subsequently been approved for specific experiments using REX-ISOLDE beams. It is expected that REX-ISOLDE will start operation next year and the Committeeconsidered that the first priority is to make it operational, after which that part of the backlogassociated with the experiments approved since 1995 can be considered. By the next meeting, theCommittee will therefore review the status of the original allocation with the goal of arriving at agood estimate of the number of shifts required for commissioning REX-ISOLDE and for carryingout one or two initial demonstration experiments.GENERAL DISCUSSIONAfter these experiment-by-experiment discussions, the ISTC discussed more generally what stepscould be taken to avoid perpetuating the situation that has resulted in the present backlog. Thefollowing possibilities were discussed:1) Concerning the present backlog, ongoing projects to be subject to review by the ISTC on aregular basis. In particular, all experiments approved before 1997 to be reconsidered in2000.2) Limitation of the validity of the attribution of shifts to any future experiment to a period ofthree years (this being approximately the period over which the entire membership of theCommittee changes). The three-year period would begin on the date the experiment wasapproved, and outstanding shifts at the end of the period would be cancelled. Prolongationof the activity would require a new proposal (or an addendum) to the ISTC with anappropriate request for a new allocation of shifts.. 44It was agreed to reconsider these points at the next meeting with a view to adopting them formallyas general guidelines for future proposals.OTHER BUSINESS:It was pointed out that the Committee's ISTC acronym is already well-established for theInternational Science and Technology Centre in Moscow. From January 1, 2000, the Committeewill therefore be known as the INTC (ISOLDE-Neutron Time of flight Committee).The Committee has received the following ISOLDE proposals:ISTC 99-4/P115: Diffusion Mechanisms and Lattice Locations of Thermal-Equilibrium Defects inSi-Ge Alloys.ISTC 99-5/P116: Isospin mixing in N »  Z Nuclei.IS359 (ISTC 99-6/P85 Add.1): Investigations of Deep-Level Fe-centres in Si by MössbauerSpectroscopy.As remarked above, open presentation of these proposals has been deferred to a forthcomingmeeting.Dates for meetings in 2000:February, 28–29May 15–16September 25-26November 27–28.J. EadesISTC Secretary, Tel.76 74273John.Eades@cern.chISTC    Secretariat:  Monique Budel (Bldg. 14/4-022)  Tel.76 74270Monique.Budel@cern.ch

Minutes of the second meeting on Monday 29th November 1999

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