First γ-decay studies with CARIBU
low-energy exotic beams
AJ	  Mitchell	  University	  of	  Massachusetts	  Lowell,	  USA

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Advances in Radioactive Isotope Science 6 June 2014

CARIBU:	  CAlifornium	  Rare	  Isotope	  Breeder	  UpgradeG.	  Savard	  et	  al	  Nucl.	  Inst.	  and	  Meth.	  in	  Phys.	  Res.	  B	  266	  (2008)	  4086–4091

252Cf	  3.1	  %	  s.f.	  branch	  	  T1/2	  ≈	  2.6	  yrp-­‐induced	  238U	  	  fission	  regions
possible	  	  r-­‐process	  	  path

OpportuniNes	  for	  study	  in	  a	  range	  of	  areas:	  Structure	  -­‐>	  features	  of	  large	  neutron	  excesses	  Astrophysics	  -­‐>	  mass/half-­‐lives	  of	  r-­‐process	  nuclei	  ApplicaNons	  -­‐>	  decay	  heat
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Mass	  distribuNons	  of	  	  233,235U,	  239Pu	  thermal-­‐neutron	  ﬁssion	  and	  252Cf	  spontaneous	  ﬁssion	  A.C.	  Wahl,	  Symposium	  on	  Physics	  and	  Chemistry	  of	  Fission	  (1965)

Guy	  Savard:	  The	  CARIBU	  facility	  (Tuesday	  Plenary	  6)Advances in Radioactive Isotope Science 6 June 2014

The	  CARIBU	  hall	  @	  ANLGas	  catcher
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Low-­‐Energy	  experiments

Cooler/buncher

To	  ATLAS

Charge	  	  breedingh"ps://www.phy.anl.gov/atlas/caribu/index.html

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The	  CARIBU	  hall	  @	  ANLGas	  catcher
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Low-­‐Energy	  experiments
CARIBUhigh-voltage
platform

Switchyard

Cooler/buncher
X-Array/SATURNTo ATLAS

To Low-Energy
To	  ATLAS
experiments

KickerStub-line
tape station

Charge	  	  breeding

CPT tower and electronics

h"ps://www.phy.anl.gov/atlas/caribu/index.html

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The	  CARIBU	  hall	  @	  ANLGas	  catcher
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Low-­‐Energy	  experiments

Low-­‐energy	  Science	  • β-­‐γ-­‐t	  and	  β-­‐γ-­‐γ	  spectroscopy	  CARIBU
high-voltage
platform

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Cooler/buncher
X-Array/SATURNTo ATLAS• T1/2	  measurements	  To Low-Energy
To	  ATLAS
experiments

KickerStub-line
tape station

CPT tower and electronics• Mass	  measurements	  (CPT)	  Charge	  	  breeding• β-­‐delayed	  neutron	  emission	  (BPT)	  • Total	  Absorption	  Gamma-­‐ray	  Spectroscopy	  (TAGS)	  h"ps://www.phy.anl.gov/atlas/caribu/index.html

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The	  CARIBU	  hall	  @	  ANLGas	  catcher
CARIBU
Isobar	  separator

Low-­‐Energy	  experiments

Low-­‐energy	  Science	  • β-­‐γ-­‐t	  and	  β-­‐γ-­‐γ	  spectroscopy	  CARIBU
high-voltage
platform

Switchyard

Cooler/buncher
X-Array/SATURNTo ATLAS• T1/2	  measurements	  To Low-Energy
To	  ATLAS
experiments

KickerStub-line
tape station

CPT tower and electronics• Mass	  measurements	  (CPT)	  Charge	  	  breeding• β-­‐delayed	  neutron	  emission	  (BPT)	  • Total	  Absorption	  Gamma-­‐ray	  Spectroscopy	  (TAGS)	  h"ps://www.phy.anl.gov/atlas/caribu/index.html

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The	  “X-­‐Array”	  @	  CARIBU
0.5

X-­‐Array	  +	  β	  detector

Absolute photopeak efficiency

X-­‐Array

0.1

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SimulaNons	  from	  	  N.	  D’Olympia	  (UML)
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Excitation energy (keV)• Five	  HPGe	  clover	  detectors	  	  4	  of	  60x60	  mm	  and	  70x70	  mm	  SuperClover	  • Large	  solid-­‐angle	  coverage	  ~	  65	  %	  of	  4π	  • High	  photopeak	  efficiency	  	  ~50	  %	  @	  122	  keV,	  ~10%	  @	  1332	  keVLearning with Purpose

Advances in Radioactive Isotope Science 6 June 2014β-­‐particle	  detection“Mark	  1”	  chamber

CollimaNon

4	  PMT	  modules

6-­‐mm	  Al	  chamber10-­‐cm	  dia.	  x	  10-­‐cm	  long	  BC-­‐408	  plasNc	  scinNllator

Light	  guides

6-­‐mm	  thick	  BC-­‐408	  plasNc	  “paddles”

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Advances in Radioactive Isotope Science 6 June 2014

Long-­‐lived	  radiation	  removal“SATURN:	  ScinNllator	  	  And	  Tape	  Using	  RadioacNve	  Nuclei”• Hardware:	  Good	  vacuum	  properties	  Motor/pulleys/belts	  etc	  Storage	  for	  excess	  tape	  Chamber	  modifications	  • Control	  system:	  Motor	  controller	  PLC	  DDAQ	  +	  electronics
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Smooth roller

Tension feedback
mechanism

Toothed sprocket

Tape-storage unit

Advances in Radioactive Isotope Science 6 June 2014

Commissioning	  (large-­‐volume	  detector)
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X-­‐Array+SATURN
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1500

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33No	  apeNottapemotion
TapemotionTape

3146Ba

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Eγ (keV)• 142-­‐146Cs	  -­‐>	  142-­‐146Ba	  γ-­‐singles,	  β-­‐γ	  γ-­‐γ,	  βγγ	  coincidences	  With/without	  tape	  γ-­‐t,	  β-­‐γ-­‐tAdvances in Radioactive Isotope Science 6 June 2014

Commissioning	  (paddles	  —	  last	  week)
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Advances in Radioactive Isotope Science 6 June 2014

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Determining	  decay	  half-­‐lives
Stub-­‐line	  tape	  staNon

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Cs→142Ba, Run #2, Eγ = 359 keV

Courtesy	  of	  Peter	  Bertone

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χ /n=
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5DecayDecay

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Advances in Radioactive Isotope Science 6 June 2014

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1200140160Modularity	  of	  the	  X-­‐Array	  —	  CLYC
Pulse-shape Discrimination (PSD)

Cs2LiYCl6:Ce	  	  	  (CLYC)
6Li(𝑛,α)3H-­‐	  Thermal/fast	  n

35Cl(𝑛,𝑝)35S-­‐	  Fast	  nOp^mized	  for	  fast	  neutron	  detec^on	  by	  using	  6Li-­‐depleted	  (~99.3%	  enrichment	  of	  7Li).	  	  Suppresses	  thermal	  and	  epi-­‐thermal	  neutron	  response.	  

Replace one
clover with
C7LYC pack

Crystals	  grown	  by	  RadiaNon	  Monitoring	  Devices	  Inc.	  (RMD)

Courtesy	  of	  Nathan	  D’Olympia
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Advances in Radioactive Isotope Science 6 June 2014

PAC-­‐approved	  experiments	  ready	  to	  goAvailable	  on	  the	  web	  @	  h"p://www.phy.anl.gov/atlas/pac/app_exp.html

Learning with Purpose

Advances in Radioactive Isotope Science 6 June 2014

	  Collaboration
UMass	  Lowell:	  	  AJ	  Mitchell*,	  CJ	  Lister,	  P	  Chowdhury,	  P	  Copp,	  AY	  Deo,	  	  N.	  D’Olympia,	  RD	  Harding,	  R	  Shearman	  Argonne	  NaNonal	  Laboratory:	  	  AD	  Ayangeakaa,	  M	  Albers,	  PF	  Bertone,	  MP	  Carpenter,	  JA	  Clark,	  HM	  David,	  B	  DiGiovine,	  RVF	  Janssens,	  FG	  Kondev,	  J	  Rohrer,	  	  G	  Savard,	  D	  Seweryniak,	  S	  Zhu	  Brookhaven	  NaNonal	  Laboratory:	  EA	  McCutchan,	  	  A	  Sonzogni	  Florida	  State	  Univeristy:	  	  SL	  Tabor,	  R	  Dungan	  Univeristy	  of	  Maryland:	  WB	  Walters,	  CJ	  Chiara,	  J	  Harker	  	  Lawrence	  Berkeley	  NaNonal	  Laboratory:	  J	  Rissanen	  Vanderbilt	  University:	  AV	  Ramayya,	  S	  Liu,	  Y	  Wang*	  Email:	  Alan_Mitchell@uml.edu

Funded	  by	  the	  DOE	  Oﬃce	  of	  Science
Learning with PurposeAdvances in Radioactive Isotope Science 6 June 2014

	  Collaboration
UMass	  Lowell:	  	  AJ	  Mitchell*,	  CJ	  Lister,	  P	  Chowdhury,	  P	  Copp,	  AY	  Deo,	  	  N.	  D’Olympia,	  RD	  Harding,	  R	  Shearman	  Argonne	  NaNonal	  Laboratory:	  	  AD	  Ayangeakaa,	  M	  Albers,	  PF	  Bertone,	  MP	  Carpenter,	  JA	  Clark,	  HM	  David,	  B	  DiGiovine,	  RVF	  Janssens,	  FG	  Kondev,	  J	  Rohrer,	  	  G	  Savard,	  D	  Seweryniak,	  S	  Zhu	  Brookhaven	  NaNonal	  Laboratory:	  EA	  McCutchan,	  	  A	  Sonzogni	  Florida	  State	  Univeristy:	  	  SL	  Tabor,	  R	  Dungan	  Univeristy	  of	  Maryland:	  WB	  Walters,	  CJ	  Chiara,	  J	  Harker	  	  Lawrence	  Berkeley	  NaNonal	  Laboratory:	  J	  Rissanen	  Vanderbilt	  University:	  AV	  Ramayya,	  S	  Liu,	  Y	  Wang*	  Email:	  Alan_Mitchell@uml.edu

Funded	  by	  the	  DOE	  Oﬃce	  of	  Science
Learning with Purpose

Advances in Radioactive Isotope Science 6 June 2014

Please	  note…
To	  the	  experimentalists:	  !
We	  welcome	  further	  collabora^on,	  so	  if	  you	  are	  interested	  please	  let	  us	  know	  !
!
To	  the	  theorists:	  !
If	  you	  would	  like	  us	  to	  measure	  something,	  please	  let	  us	  know

Learning with Purpose

Advances in Radioactive Isotope Science 6 June 2014

Thank	  you	  for	  your	  a"en^on
ありがとう。

Learning with Purpose

Advances in Radioactive Isotope Science 6 June 2014