- On September 21st, the NeuLAND demonstrator, consisting of four double-planes, came back to GSI after a two-years campaign at RIKEN, see photos below.
- A campaign of three experiments has been carried out using the SAMURAI setup and the NeuLAND demonstrator, devoted to studies using 8He and 6He beams.
- During spring the NeuLAND demonstrator was used in two experiments at SAMURAI: Dipole response of neutron-rich Ca isotopes and the SEASTAR3 campaign.
- At GSI the assembly of NeuLAND double plane 11 was completed. Two more double planes will be built during 2017, which leads to more than 40% completion of NeuLAND for the phase 0 programm at GSI starting in 2018.
- On Feb. 28th the NeuLAND Working Group Meeting took place in conjunction with the NUSTAR Week at GSI. The agenda comprised reports about experiments with the NeuLAND prototype and demonstrator at GSI and RIKEN, simulation studies both on the detector performance as a function of detector depth and the possible need for a VETO detector in front of NeuLAND, the status of NeuLAND production and the upcoming experiments at RIKEN in 2017 followed by the backtransport to GSI and the preparation of the experimental campaign starting in 2018 at GSI.
- For the autumn 2016 measurement campaign at SAMURAI, the NeuLAND demonstrator has been moved back to its position at 0 degree to the beam line. Three experiments have been carried out using light ions, comprising a study of the unbound states and ground-state properties of 31Ne, an investigation of the level structure of 22C combined with the search for 21B, and an experiment exploiting a new technique to determine the neutron-decay lifetime of the 26O ground state.
- The pre-series of the new read-out electronics for NeuLAND - NeuLAND-TAMEX (200 channels) was mounted inside the electronic boxes of one double-plane and successfully taken into operation. This electronics is a GSI in-house development based on the former TacQuila electronics. It delivers a very precise time measurement from an FPGA TDC and a charge measurement using the Time-over-Threshold (ToT) method. The timing properties of the double-plane, determined using cosmic rays, exhibit results of typically 120 ps (sigma) similar to earlier extracted values using the former electronics. Based on these results, the mass production of this cost-effective solution will be launched.
- The first part of the series production of the high-voltage distribution system (HVDS) for NeuLAND was delivered to GSI/FAIR and successfully taken into operation. The delivery comprises 20 modules, each serving 50 PMTs of NeuLAND, thus 1000 channels. The HVDS is developed, produced and delivered by PNPI, Russia, and the design has been optimized for usage with NeuLAND. The second delivery comprising 2000 channels is scheduled for autumn 2017.
- The NeuLAND demonstrator was part of the Sπrit TPC experiment carried out at RIKEN. In contrast to earlier experiments, the NeuLAND demonstrator joined, here, the detector seeing both charged particles and neutrons stemming from central collisions of 108,112,124,132Sn on 112,124 Sn target.
Figure 1 shows a particle ID plot from the 1st NeuLAND plane, displaying the time of flight over the energy deposited in the hit. Protons, deuterons, tritons, 3He and 4He were identified.
Figure 2 shows the same distribution, but including a condition that no VETO hit was registered in the event.
The left-over distribution is originating from neutrons and (at small time of flights) gamma-rays.
Besides the main goal, the derivation of neutron over charged particle ratios for the Sπrit TPC experiment, the data taken are of great value for detector response studies, having charged and neutral particles hitting the detector at the same time.
The NeuLAND demonstrator, currently located at RIKEN , Japan, was moved within the SAMURAI Area to 30 degrees with respect to the target, see photo below. At this new position, NeuLAND together with a VETO wall in front will take data in an upcoming experiment, studying central collision in several combinations of Sn isotopes beams and Sn isotope targets.
- The status of the analysis of the 7Li(p,n) calibration experiment of the NeuLAND Demonstrator at RIKEN (see NeuLAND news Nov. 2015) is summarized in an RIKEN progress report. The figure below shows the preliminary experimental velocity spectrum of NeuLAND for ~ 110MeV neutrons with veto condition cut, and an energy cut E > 5MeVee. The background was evaluated with an empty-target run. The integral under the red curve indicates the neutron events, which will be used to derive the efficiency.
On March 1st the NeuLAND Working Group Meeting took place with about 30 participants at GSI. In the first session the status and the preparations needed for NeuLAND up to the experimental campaign to be started in the beginning of 2018 was summarized. The progress of detector construction was discussed as well as the HV supplying system and the readout electronics. Measures to be taken concerning the data acquisition and slow control, simulations, analysis and calibrations were specified. In the second session the status of the analysis of data from the last experiments and the ongoing progress in simulations were presented and discussed.
The first of the two NeuLAND frames has been built, see photograph. It allows to hold up to 20 double planes. Its design allows the junction with a second frame to support all foreseen 30 NeuLAND double-planes, but also allows the splitting of the detector in two independent components and placing at different distances and angles to the target, depending on the specific experimental demands. The service platform, visible in the technical drawing on the right side is currently under construction.
- Preliminary online analysis of NeuLAND data measured at RIKEN are very promising: An efficiency of (31.5±1.1)% for one-neutron events is extracted from the preliminary analysis for the 250 MeV neutron run for the NeuLAND configuration at RIKEN (4 double-planes, 40 cm of detector depth); this result is in good accordance with simulation (29%).
- The figure below shows the paddle multiplicity summed over all NeuLAND and Nebula modules for two different incoming ions at 250 AMeV. For the (p,3p) reaction of 29Ne, three neutrons are emitted in forward direction, for the (p,2p) reaction of 29F four neutrons impinge on the neutron detectors. A clear increase in paddle multiplicity was observed online, indicating the higher number of neutrons detected. The unambigious identification of the number of neutrons and their momentum reconstruction requires a more complex offline analysis.
Part of the NeuLAND detector is presently in operation as one major components in an experimental campaign performed with the SAMURAI setup at RIKEN, studying several exotic neutron-rich nuclei including the double-magic nucleus 28O. The experiments are complemented by a calibration experiment for the combination of NeuLAND and NEBULA (the neutron detector at the SAMURAI setup), determining the efficiency at neutron energies of 110 and 250 MeV.
- On June 1st the status of the NeuLAND subproject was presented during the R3B collaboration meeting. An update on the status was given for the production of double-planes at GSI, the planned in-kind contributions from PNPI and the design of the NeuLAND electronics. The planned experimental campaign at RIKEN was discussed and very first simulations on a VETO concept for NeuLAND were presented. The session closed with a presentation on the latest findings from the SiPM study for a possible use at later stages of the NeuLAND project.
- Seventh double-plane of the NeuLAND detector has been built.
- The four NeuLAND double-planes located at the SAMURAI setup at RIKEN have been successfully taken into operation and the calibration using cosmic rays has been performed. Next steps are the combined data taking with the NEBULA Veto Wall and with the NEBULA Detector itself.
- In connection with the NUSTAR week a NeuLAND working group meeting on March 3 at GSI discussed the future analysis framework for R3B, status of NeuLAND@RIKEN and future experiments there. Presentations on the status of the the analysis of S406 and S438a-c as well as on needed simulations were given. The performance of SiPMTs, which might become in the future an alternative for conventional PMTs, was presented.
- On February 15th the four double-planes of the NeuLAND detector have been integrated into SAMURAI setup.
- At GSI the double plane 6 has been assembled in its final configuration.
- On January 12th, the box containing the four NeuLAND double-planes has left GSI (see picture below, left) and has arrived on January 27th at RIKEN. On January 31st the box has been transported down to the SAMURAI cave, see photo below right.
- The first high-voltage distributors for the neutron detector NeuLAND within the FAIR research collaboration NUSTAR have arrived from Russia’s Petersburg Nuclear Physics Institute (PNPI) and have been tested in a combined effort from the PNPI and GSI teams.
This pre-series comprises four HVDS modules, serving in total one NeuLAND double-plane (200 PMT channels). Up to 2017 the full detector shall be equipped with the PNPI distribution system.
A more detailed report including some photographs was published in the FAIR News.
- After the successful beam times at GSI, four NeuLAND double-planes, its electronics and high voltage supplies are dismounted and prepared for shipping to RIKEN. During the planned two-years stay this NeuLAND sub-unit will be used in several experiments at SAMURAI.
- The NeuLAND demonstrator was taking part in two GSI beam times - S438 and S412 in Cave C. During Oct 2nd to 9th the second part of the S438 experiment took place testing various demonstrators and prototypes of the R3B components using 48Ca beam. NeuLAND was exposed to neutrons from nuclear breakup of Ca on C target primarily, therefore dominantly one- and two-neutron events are expected. The figure below displays, as an example, the spatial hit distribution perpendicular to the beam axis in four NeuLAND double planes; the position information is derived in one direction from the detector modularity (bar number), in the other direction from the time difference of the two photomultipliers (PMTs) reading out each submodule. Of special interest are the multi-neutron events expected from fission studies during the SOFIA experiment S412 performed during Oct 17th to 25th at R3B/GSI. In addition, important information on background handling in NeuLAND was gained during the three GSI beam times during this year.
- The NeuLAND demonstrator has been assembled for the October beam times ahead. The demonstrator comprises five so-called double-planes and thus 1/6 of the total NeuLAND detector. For the electronics read-out four double-planes have been equipped with TacQuila electronics inherited from the LAND detector, the fith double-plane will be read out with a prototype of the NeuLAND electronics under development.
- NeuLAND made it to the cover of the GSI Magazine "target". For more detials, see here.
- PNPI (Petersburg Nuclear Physics Institute) and FAIR GmbH have signed a Collaboration Contract on „The production and delivery of the High Voltage Distribution System for the NeuLAND detector and the development of the EPICS IOC application software“. The 6000 Photomultiplier Tubes (PMTs) of NeuLAND will be served from two „HV3200“ systems which allow the individual down-regulation of one primary high voltage power-supply-output voltage for each PMT. Fifty channels are comprised within one distribution board, thus, four distribution board serve one NeuLAND double plane, being located on the double plane frame structure. The pre-series (200 channels) will be delivered up to end of this year. The production of the full distribution system is divided in several batches up to 2017.
- The NeuLAND detector, its working principles and its aims is introduced to the broad public in a press release. NeuLAND appeared on the start page of GSI from July 24th on under the title "Unmasking neutrons with NeuLAND". The newspaper Darmstaedter Echo dedicated an elaborated article named „Ein Funkeln enttarnt Neutronen“ on July 29th to our project, online available with the title „Neutronendetektor für den Teilchenbeschleuniger Fair“.
- Preliminary analysis of the S438 data has resulted in a 100 ps time resolution for the gamma peak. Measurements have been performed using 700 AMeV 58Ni beam and a Pb target. In the same time, using the charge-particle veto x- and y-position of the neutrons impinging in the NeuLAND prototype, see figure below, have been obtained.
- The housings in which the electronic cards will be positioned have been designed and produced, see photo below.
- During the S438 experiment the prototype of the NeuLAND detector has been tested. Measured data are under anaylsis.
- Two new NeuLAND double-planes have been built. Up to now, 300 scintillator bars and 600 photomultipliers have been built in 3 double planes. Three additional planes are planned to be built along 2014.
- The second charge of the NeuLAND scintillator bars has been delivered to GSI.
- The high voltage distribution boards have arrived at GSI. These boards allow to distribute the HV to each PM and collect the signal cables at the same time. The connectors will allow an easy substitute of photomultipliers.
- The first charge of the NeuLAND photomultipliers has been delivered by HAMAMATSU and arrived to GSI. The photomultipliers are of the type R8619 AVD-ASSY. They have fully active base resulting in a very low operation current, a requirement for the practicable use of the 6000 PMs, which NeuLAND detector will have in its final stage. The photomultipliers will be connected to the HV distribution system via printed circuit boards.
- The first charge of the NeuLAND scintillator bars has been delivered by Rexon and arrived to GSI.
- The mounting rack which will be used for assembling the NeuLAND planes has been constructed and delivered to GSI, see figure below. It is installed in the NeuLAND tent on top of the ESR. Its functionality, e.g. possibility to easy hang, access and move NeuLAND planes has been successfully tested.
On May, 13th the NeuLAND Working Group meeting took place at GSI. NeuLAND WG members from Universities of Cologne, Darmstadt, Frankfurt and Lisbon joined the meeting together with the collaborators from Chalmers, Gothenborg, HZDR Rossendorf and from LIP Coimbra, hosted by the GSI project team.
The first session focussed on recent and next steps towards the 20% demonstrator of NeuLAND which shall be assembled by the end of this year. The topics discussed comprised the status of tendering, framework contracts and the funding situation, both for the 20% and for the full NeuLAND detector. Concerning quality control during the production phase, testing procedures for the scintillator bars using electron beams, LED`s and sources have been presented
In the second session the preliminary results of the neutron-calibration experiment S406, carried out on a NeuLAND test assembly in November 2012 were reported and compared to simulations. Excellent agreement is found between measured data and simulation performed using FairRoot, see figure (a) below. Data traces from neutrons in the NeuLAND test array, as presented in figure (b) below, serve as important input for the further development of the neutron recognition algorithm for the final NeuLAND detector.
In the NeuLAND session of the R3B meeting on May 14th condensed reports covering the topics in the WG meeting were given. In addition the news on NeuLAND mechanics like the building of the first NeuLAND double-plane and the design of the mounting rack were presented. The newly designed read-out electronics for NeuLAND, based on a custom electronics solution implementing an FPGA TDC with a time-over-threshold measurement with an optical readout has been presented. The system is based on the previous Tacquila electronics and benefits from the already adpated front-end board together with a system board that features trigger generation, signal monitoring and controls. Moreover, details on the planned custom-made HV distribution system for the 6000 photomultipliers of NeuLAND were given.
NeuLAND WG members can find the minutes and talks from the meeting in the NeuLAND elog.
- The first double-plane of the NeuLAND detector has been assembled at GSI. One double-plane contains 50 vertical and 50 horizontal bars. The active size of one scintillator bar is 5x5x250 cm3. The frame holding a double-plane is made of aluminium and supports also boxes containing read-out electronics and HV distribution system. The whole double-plane has a weight of 760 kg. In the figure below, different stages of the double-plane assembly can be seen.
- Mounting rack that will be used for assembling the NeuLAND planes has been designed (see picture below) and ordered. It will also be possible to use the rack during the experiments as it can contain up to six NeuLAND double-planes.
- On January 18 FAIR has approved the NeuLAND Technical Design Report following the recomendation of the FAIR Expert Comittee Experiments. The NeuLAND TDR can be found at the following link.
- On November 19 the FAIR Expert Comittee Experiments has aproved the NeuLAND technical design report.
- Preliminary analysis of the NeuLAND data measured in the S406 experiment with 2H beam has resulted in an time resolution of the NeuLAND detector of 114 ps, see below.
- At the beginning of October 2012 an assembly of 100 bars has been built, see figure below left. Bars have been tested with cosmic rays, and in best cases a time resolution of 130 ps has been reached.
- Mid of October additional 50 bars have been arrived and have been added to the NeuLAND test assembly. The whole setup has been moved (see figure below right) to Cave C in order to be tested with neutrons (experiment S406).