Proposals to be submitted to the Program Advisory Committee
must be received on or before July 13, 2003.
Detailed instructions including important dates may be found on our
website. A list of
including expected intensities is also available.
Some web-based programs may also be beneficial to your planning:
major experimental endstations and on
may be found in previous HRIBF Newsletters. The
membership of PAC-9 is also available.
We encourage you to contact us with
suggestions for the beams you require to pursue your physics research.
as to what constitutes a suitable beam for the HRIBF
may be found in our more recent newsletters.
We ask that you need to be aware that scheduling experiments at our
facility is difficult. In some cases such as transfer experiments, suitable
equipment is not yet in place to take full advantage of the allocated
beam time. In other cases, sufficiently many experiments must be available
before it is "cost effective" to schedule a particular RIB ion source
or endstation configuration.
Additional information reflecting the present status of equipment and
techniques is provided below or may be found from our recent
- Information from previous PACs
- Neutron-rich RIB Development - An update
The last neutron-rich RIB campaign saw several highlights:
For more information contact Paul Hausladen at
Dan Stracener at
- 132Sn yields on target exceeded
105 i/s for double-stripped beams
and 8.5x105 i/s
for single-stripped beams. The purity of these beams was >95% by
using SnS molecular transport.
- 134Sn yields on target exceeded
2000 i/s for single-stripped beams and was mixed with 6000 i/s
of Sb and Te isotopes. SnS was used.
- 82Ge yields on target exceeded
2x104 i/s for single-stripped beams.
The purity was enhanced to 22% by using GeS molecular transport.
- Beams of exotic nuclei such as
77,78,79Cu have been observed at
rates of 1.5 i/s, 0.15 i/s and 20 i/h, respectively. These rates
were observed after tandem acceleration to ~3 MeV/u and should be
at least a factor of 10 higher since the experiment was
overall countrate limited to 5000 i/s. In addition,
86Ge has been observed at the 20 i/h
level. Although small, these rates are larger than most fragmentation
facilities. They are heavily contaminated.
- 132Te single-stripped beam on target
had a sustained rate of 3x107 i/s.
- Proton-rich RIB Development - An update
We are planning a series of experiments using
7Be beams. A
sputter ion source has been developed to hold up to 8 pellets.
The anticipated beam intensity is on the order of
We have not produced the
here so any potential user will be required to locate a source for the
Other proton-rich beams are in various stages of development. We
anticipate being able to deliver approximately
2x103 i/s on target of
1x103 i/s on target of
4x103 i/s on target of
34Cl. It should be noted that
these beams have not been accelerated through the tandem and we
are assuming 10% transmission to the target. More
development work is planned. Significantly higher beam requirements
would be viewed as a Letter of Intent.
For more information contact Dan Stracener at
- Generic beamlines
We presently have two beamlines which may support small experimental
setups and a third one is in the planning stages. All lines end in either
4-inch conflat and/or 8-inch large flange ports. Cryopumps are presently
used for vacuum. One beamline supports the 1-meter scattering chamber
(see below) while the other is presently used for fusion-evaporation
cross-section measurements. The third beamline will house the
Spin Spectrometer (see below) but because it will be the same
height as the other beamlines, small user setups should also fit when the
Spin Spectrometer is open.
For more information contact Felix Liang at
Dan Shapira at email@example.com.
- Spin Spectrometer
We have plans to rejuvenate the Spin Spectrometer, a 72-element NaI detector
array with 4-pi coverage. An initial scan of the detectors suggests most
can hold voltage and produce signals. Presently, we anticipate that the
energy resolution will be on the order of 10%, sufficient for low countrate
experiments with a low density of transitions. The array will be housed
on a new beamline (see above). At present, only Letters of Intent should
be submitted requiring this detector array. Further investment into the array
will depend on the level of interest and initial results.
For more information contact David Radford at
- Windowless gas cell
The windowless gas cell will undergo commissioning this summer. Beam has
been passed through the cell and reaction products detected at the
DRS focal plane. Characterization (density measurements) of the cell will
begin shortly; we hope the cell will be used with hydrogen later in
the summer. First experiments with the cell are planned for winter.
For more information contact Jeff Blackmon at
- Forward Array
The forward array is awaiting delivery of constant fraction modules.
A prototype CFD was delivered and tested but additional flexibility
was desired to make the module useful for a wider range of detectors.
We hope the first layer of the forward array will undergo inbeam testing
For more information contact Alfredo Galindo-Uribarri at
- Small Csi detector array
A 5-ring CsI array has been ordered and will substitute for the
4-pi CsI HyBall for COULEX experiments. This detector will be
used without absorbers for improved response with heavy nuclei.
In the COULEX experiments, target atoms which are knocked out of
the target are used to identify COULEX events.
For more information contact Alfredo Galindo-Uribarri at
- Neutron detector array
A 20-element neutron detector array has been purchased from SCIONIX.
Each detector contains 1.47 liters of the liquid scintillator LS-301
(similar to NE-213). The detectors are in house, the support structure
is under construction, and prototype electrons have been delivered
by RIS Corp. We estimate that the array will have an efficiency of
around 20%. We hope the array will be available for experiments
next winter. For more information contact
Chang-Hong Yu at firstname.lastname@example.org.
- Scattering chamber
A 1-meter diameter, 30 cm deep scattering chamber will be installed this
summer. At present, it is "bare bones" and users will be expected to
help with detector mounts, electrical feedthroughs, etc. We do have
a good vacuum system and target ladder. For more information contact
Felix Liang at email@example.com.
- Enge in gas-filled mode
The Enge focal plane is being outfitted with a double-sided silicon strip
strip detector mounted on a 10-inch OD flange. This detector system
will be used for decay studies and in Enge gas-filled mode.
For more information contact
Felix Liang at firstname.lastname@example.org
or Kris Rykaczewski at
- Decay spectroscopy detectors
The proton emitter setup has been expanded to include a four detector
Si box situated on the forward side of a DSSD. Proton and alpha
particles which exit the DSSD will strike these veto-detectors providing
suppression of the low-energy background events. Each detector is
50 mm square and 700 um thick. In addition, a 4.5 mm thick, 45 mm square
Si(Li) detector sits behind the DSSD and will be used to detect betas.
The CARDS set-up may also contain BESCA, Bellows Electron Spectrometer for
the CARDS Array, a 5-mm thick,
200 mm2 Si(Li) detector
used to identify conversion electrons. The setup is designed to replace
one of the four Clover Ge detector typically used with CARDS. The bellows
system allows easy access to the vacuum chamber without warming BESCA.
- Microchannel plates at final focus of the RMS
A large MCP detector has been purchased, tested successfully, but then
developed a problem. The detector was returned to the manufacturer and
new plates were installed. We expect delivery soon and hope that the new
large-area MCP will be operational prior to PAC-9.
For more information contact Carl Gross at
- Data acquisition
We are quickly moving to LINUX machines for our data acquisition
and analysis computers. These replace our DEC Alpha machines.
In the new system, data will be written directly to disk on a
new 2-terabyte server. For transport to the user's home, we
offer DVD writers (-R,-RW formats) which hold roughly 4.3 GB of data
or the usual Exabyte tapes. Users are expected to bring their
own DVDs and tapes. Tapes will be slowly phased out.
For more information contact Robert Varner at