light element studies structure of transfermium nuclei

Light element studiesStructure of transfermium nuclei

Darek Seweryniakon behalf of ANL, Lowell, Jyvaaskyla, Maryland, Orsay, … collaboration

Argonne National LaboratoryATLAS User Workshop, May 15-16, 2014

Heavy element studiesStructure of transfermium nuclei

Darek Seweryniakon behalf of ANL, Lowell, Jyvaaskyla, Maryland, Orsay, … collaboration

Argonne National LaboratoryATLAS User Workshop, May 15-16, 2014

3

neutron number

111112113

114

117

115

118

116

160 162

164 166 168 170 172 174

176 178 180 182 184

152 158156154

Mt 266

Db 262 Db 263

Sg 266

Db 258Db 256 Db 260Db 257

Rf 260 Rf 261 Rf 262 Rf 263Rf 259Rf 256Rf 255 Rf 258

Bh 261 Bh 262

Rf 257

Db 261

Sg 260 Sg 261 Sg 263Sg 259

Bh 264BhHs

Ds

Sg 258

Lr 259

No 258

Lr 260

No 259

Lr 261 Lr 262

No 262No 260

Lr 258

No 257

Lr 255

No 254

Lr 254

No 253

Lr 257

No 256

Lr 256

No 255

Md 257

Fm 256

Md 258

Fm 257

Md 259 Md 260

Fm 258 Fm 259

Md 256

Fm 255

Md 253

Fm 252

Md 252

Fm 251

Md 255

Fm 254

Md 254

Fm 253

Es 255 Es 256Es 254Es 251Es 250 Es 253Es 252

Cf 255 Cf 256Cf 253Cf 250Cf 249 Cf 251 Cf 252 Cf 254

110/273110/271

111/272

CHART OF THE NUCLIDES

NoMdFmEsCf

pro

ton

n

um

ber

150

DbRfLrNoMdFmEsCf

Z = 114

108Hs 267Hs 265Hs 264

a

aa

aa

a

110/270

Hs 266

Sg 262

112/2859.1539 s

Z/A

T1/2

E (MeV)

110/269

Mt 268

EC

-

SF

112/277

110/267

MtHs 269 Hs 270

Sg 265Sg

aaa

aa

aa

aa

aa

a

aa

a aa

aaaa

108/275

110/279

106/271

112/284112/282

114/286114/28710.01

114/2889.95

116/290

115/288115/287

113/284113/283

111/280

109/276

107/272

111/279

109/257

116/29110.85 10.74

112/285

110/281

114/2899.82

9.169.54

9.30

8.53

10.00

10.4610.59

10.12

9.75

9.71

9.02

10.37

10.33

105/268

15 ms

32 ms 87 m s

6.3 m s

0.1 s

0.15 s

0.17 s

0.72 s

9.8 s

16 h

9.7 m s

0.48 s

0.1 s0.5 m s

3.6 s

0.18 s

2.4 m in

9.6 s

34 s

0.56 s 0.63 s 2.7 s0.16 s10.20

112/2834.0 s

a116/29210.6616 ms

107/217

116/29353 ms

1.8 ms118/29411.65

105/2671.2 h

10.53

9.70

104/268104/2672.3 h

48 238 249Ca + U.... Cf

208 50 70Pb + Ti.... Zn

Chart courtesy of Y. Oganessian

Cold fusion with

208Pb, 209Bi targets

GSI, LBNL, Riken

Hot fusion with 48Ca beams Dubna/LLNL, GSI, LBNL

Super-Heavy Nuclei

In-beam, K-isomers, -decay fine structure

ANL, Dubna, GSI, JYFL, LBNL

ATLAS User meeting, May 15-16, 2014

4

Outline

Physics– Discrete in-beam -ray spectroscopy - moments of inertia, alignment– in-beam -ray calorimetry – fission barriers– K-isomers – single-particle energies– Decay spectroscopy – alpha decay Q-values, spontaneous fission lifetimes– Cooled beams

• Precision mass measurements• Laser spectroscopy

– SHE formation (W. Loveland)

Equipment– Fragment Mass Analyzer + GS– AGFA + DGS/GRETINA (higher efficiency x 10 , higher rates x 5)– intense beams from ATLAS (~1 pA)

Discrete in-beam spectroscopy


5

P. Greenlees et al., PRL 109, 012501 (2012)

256RfJUROSPHERE+RITU

In-beam spectroscopy “above” K-isomers


6

B. Sulignano et al., PRC 186, 044318 (2012)

8- isomer in 252No JUROSPHERE+RITU7/2+[624] X 9/2-[734] assignment

In-beam -ray calorimetryHK entry point distributions


7

G. Henning et al., submitted to PRL220Th

254No 219 MeV 254No 223 MeV

GS+FMA

Direct fission barrier measurement (if below neutron separation energy)

Discovery of K-isomers in 254Rfexperiments with FMA and BGS using digital DAQ


8

2qp

254Rf gs

4qpCE

CE

sf

400 s

4 s

25 s

CE-CE event

implant-CE-sf event

J. Chen, H. David, F. Kondev, D.S. et al.

SHE spectroscopy


9

D. Rudolph et al., PRL 111, 112502 (2013)

X-ray detection along the element Z=115 alpha decay chain as means to determine the atomic number

TASCA at GSI

Cool beams of heavy nuclei


10

M. Block et al., Nature 463 785 (2010)

Heavy reaction products can be stopped in a gas cell at the focal plane of AGFA, cool ed in RFQ and send to a Penning Trap.

Laser spectroscopy can be also possible (P. Mueller)

253No SHIPTRAP at GSI

Experimental requirements

DGS – high rates (x5) GRETINA – high rates (x5), large FMA solid angle (x4), Doppler correction AGFA – higher efficiency (x10), digital implantation-decay station – fast activities ATLAS intensity upgrade (x3 better beam transmission) VENUS ECR source (x5 more intense beams)


11

Detection improvements– 10x10 cm2 DSSD– in-beam CE detector

To study heavier nuclei we needmore beam, higher efficiency, faster detectors


12

Need a much easier way to move Gammasphere between the two beam lines for experiments or to avoid neutron damage during high intensity experiments.

It will make placing GRETINA on any of the two much easier as well.

Thank you for your attention.


13


14


15

Beams from protons to Uranium with energies 10MeV/nucleon+

Argonne Tandem Linac Accelerator System

See talk by Richard Pardo on Friday about radioactive beams


16

Argonne Fragment Mass Analyzer

C. N. Davids et al., Nucl. Instr. Meth., B 70, 358 (1992).


17

Argonne Fragment Mass Analyzer

Mass resolution: M/M~1/350Angular acceptance: =8 msr(2 msr)Energy acceptance: E/E=+/-20%M/Q acceptance: (M/Q)/(M/Q)=10%Flight path 8.2mMax(B)=1.1TmMax(E)=20MVCan be rotated off 0 degreesCan be moved along the axisDifferent focusing modes

Q4

Q3

ED2

ED1

MD

Q2Q1


18

GAMMASPHERE+FMA

101Sn Proton drip-line

– Proton emitters– new emitters– In-beam rays

Transfermium nuclei: No, Lr, Rf Transfer on 56Ni and 44Ti …

Important component of the experimental program at ATLAS since its commissioning in 1993 (~200 papers)

Fusion-evaporation, deep-inelastic, transfer reactions


19

ATLAS efficiency and intensity upgrade

new positive ion injector (undergoing) Two new cry modules (summer 2013) Energy upgrade cryomodule (proposed) high intensity ECR source (planned)


20

Preparation for high intensity ATLAS beams

FMA upgrades– New beam dump (completed)– New entrance quadrupole doublet (design)

Focal plane detector upgrades– Large-area high-resolution micro-channel plate detector (in progress)– High granularity DSSD (completed)

DAQ – Digital DAQ (completed)

Argonne Gas-Filled Separator (design)

Currently beams ~10 pnA, event rates ~1kHzFuture experiments ~100 pnA (1pA), event rates 10kHz(100kHz)


21

New beam dump

Segmented anode was installed in 2002 However, beam used to strike the inside of the anode and the tank

near the exit relatively close to the electrodes A suppressed beam dump was placed outside of the tank

1st electric dipole


22

New ED1 tank


23

Faraday Cup Slit in the tank wall Beam dumped on a Ta plate Entrance slit kept at positive potential with respect to the

Ta plate to suppress electrons knocked out of the plate


24

New entrance quads

1st quad shorter with larger tip field similar concept was used in EMMA Increases the solid angle from 8 msr

to 12 msr at 30 cm between target and FMA

Only small gain at 90 cm

Courtesy of B. Davids


25

FMA at 293 mmOLD:y=0.038 rad

y,max=0.0401 rad

Qx=0.046 radx,max=0.0495 rad

NEW:y=0.060 rad

y,max=0.0634 rad

Qx=0.059 radx,max=0.0591 rad

=7.4 msr =11.8 msr


26

Large-area high-resolution micro-channel plate focal plane detector detector Large area to cover the whole focal plane (4X12 cm2)

Position resolution < 1mm High rate capabilty (100 kHz) Three micro channel plates for large multiplication

D.Shapira etal., Nucl. Instr. and Meth. in Phys. Res. A 454 (2000) 409Permanent magnets to limit diffusion of electrons to achieve better position resolution

e

HI from FMA

foil

3 mcp’s

Resistive readout

magnet

Photonis Inc., USA


27

High-granularity implantation-decay DSSD

160x160 strips64mm x 64 mm100, 140, 1000 m thick


2828

X-array 5 clover detectors in a box geometry 64x64 mm, 160x160 DSSD Mobile frame


29

Trigger and Time control module

100Mhz, 14-bit Digitizer

M. Cromaz et al., A 597 (2008) 233–237

J.T. Anderson et al., 2007, IEEE Nuclear Science Symposium Conference Record, p. 1751

FMA Digital DAQ(based on GRETINA)

trigerless DSSD (320 chans) X-array (20 chans) focal plane (20 chans) Resolution comparable

to analog


30

Argonne Gas-Filled Separator - AGFA

Use combined-function magnets– Overlapping bending, focusing fields– Fewer magnets, ultra compact design– Innovative QvDm design

Design parameters– 33o bend– 22.5 msr at 80 cm (42 msr at 40 cm)– 2.5 Tm– 4.0 m total length (3.6 m at 40 cm) – 80 cm target-separator (Gammasphere)– 40 cm (stand-alone)– Compact focal plane(~5cm x 5 cm)

1B.B. Back, 1R.V.F. Janssens, 1W.F. Henning, 1T.L. Khoo, 1J.A. Nolen, 1D.H. Potterveld, 1G. Savard, 1D. Seweryniak, 3M. Paul, 2P. Chowdhury, 4W.B. Walters, 5P.J. Woods, 6K. Gregorich1Argonne National Laboratory, Argonne, 2University of Massachusetts Lowell, 3Hebrew University,4University of Maryland, 5University of Edinburgh, 6Lawrence Berkeley National Laboratory


31

AGFA optics and parameters

Quad length 48 cm

Quad bore 22 cm

Quad peak pole-tip field 1.24 T (2.5 Tm, 40 cm tgt)

Quad-dipole separation 75 cm

Dipole center gap 11 cm

Dipole bend angle 33 deg

Dipole bend radius 2.0 m

Dipole edge angle -36 deg

Dipole peak field 1.7 T (2.5 Tm)

Peak X excursion ± 30 cm

Dipole-F.P. separation 92 cm (40 cm to tgt),83 cm (80 cm to tgt)

Beam profile at target ΔX = 5.0 mm FWHMΔY = 2.0 mm FWHM

V. rays± 102 mrad

H. rays± 52 mrad


32

AGFA – 3D magnet design


33

254No test case

48Ca + 208Pb → 254No + 2nEbeam = 220 MeV

1 Torr He, 5 x 2 mm beam spot 254No angular distr: Gaussian, σ = 51 mrad 48Ca stripped, (C foil) qbar = 17.1 89% of 254No transported to focal plane 71% fall within a 64 x 64 mm2 DSSD Solid angle to DSSD is 22 msr Beam is well separated

Simulations still undergoing


34

Focal plane distribution


35


36

• A charge state acceptance : ± 10%• A Bρ acceptance for each charge state: ± 10%• A large angular acceptance in both planes: +/- 50 mrad• A magnetic rigidity Bρmax = 1.5 Tm• An electric rigidity Eρmax = 10 MV (2nd set of electrodes for higher electric rigidity)• A mass resolution of 1/300 (FWHM)• A primary beam suppression not critical

Separator for Unique Products of Experiments with Radioactive Beams - SUPERB

Based on the design of the mass separator section of S3 optimized for experiments with reaccelerated radioactive beams at Rea12

A.M. Amthor1, A. Drouart2, S. Manikonda3, J. Nolen3, H. Savajols4, D. Seweryniak3

1Bucknell University, 2CEA-DSM/Irfu/SPhN, 3Argonne National Laboratory, 4GANIL

T3QS

ED3QS

3QS

MD

3QS

FP


37

SUPERB – 1st order calculations

X-Y distribution at the focal plane for 5 charge states/3 masses

58Ni+46Ti reaction

X-Z plane

Y-Z plane


38

Conclusions

FMA is almost ready to accept high-intensity beams from ATLAS AGFA will complement FMA for experiments with heavy nuclei SUPERB combines advantages of FMA and AGFA for

experiments with reaccelerated radioactive beams


39

Thank you for your attention!


40


41


42

Argonne Gas-Filled Separator - AGFA1B.B. Back, 1R.V.F. Janssens, 1W.F. Henning, 1T.L. Khoo, 1J.A. Nolen, 1D.H. Potterveld, 1G. Savard, 1D. Seweryniak, 3M. Paul, 2P. Chowdhury, 4W.B. Walters, 5P.J. Woods, 6K. Gregorich1Argonne National Laboratory, Argonne, 2University of Massachusetts Lowell, 3Hebrew University,4University of Maryland, 5University of Edinburgh, 6Lawrence Berkeley National Laboratory

Large solid angle >15 msr Operation with Gammasphere (80 cm from target to 1st magnet) Can be operated stand-alone for larger solid angle (40 cm to 1st magnet) Bρ ≤ 2.5 Tm Good primary beam suppression

– Large bend angle Small focal spot to enable efficient measurements

– Excellent focus in vacuum mode– Short flight path to minimize growth due to multiple scattering– Small dispersion <x,δ> (cm per percent deviation in Bρ)

Cost less than $2M


43

•Target spot ± 0.5 mm in x and y with ± 50 mrad in both dimensions• Momentum acceptance ± 5% for each charge state, charge-state acceptance ± 10% , and mass range ± 10%.• Fully achromatic in momentum for each m/q value.• The first half contains an electrostatic dipole that creates an energy-dispersive focal plane. • For symmetric fusion-evaporation reactions the electric rigidities are less than 10 MV,• The second half consists of a magnetic dipole section. •The m/q focal plane is approximately 12-cm wide by 2-cm tall


44

X-array

5 clover detectors in a box geometry 64x64 mm, 160x160 DSSD


45

AGFA - Design criteria

Large solid angle >15 msr Operation with Gammasphere (80 cm from target to 1st magnet) Can be operated stand-alone for larger solid angle (40 cm to 1st magnet) Bρ ≤ 2.5 Tm Good primary beam suppression

– Large bend angle

Small focal spot to enable efficient measurements– Excellent focus in vacuum mode– Short flight path to minimize growth due to multiple scattering– Small dispersion <x,δ> (cm per percent deviation in Bρ)

Cost less than $2M


46

In some experiments the transmission is more important than the mass separation (for example SHE)

Gas-filled separators have larger angular acceptance and collect all charge states resulting in ~x5 larger transmission

Gas-gilled separators are complementary to vacuum mass separators


47

FMA Digital DAQ status

The system was already used in several experiments last spring

stand-alone FMA Conversion electrons and fission alpha decay

GAMMASPHERE+FMA Beta-decay tagging Proton-decay tagging


48

FMA Digital DAQ

IOC 4XDIG IOC 4XDIG IOC 4XDIG

IOC master TTC + 2 router TTCCPU

Router

Based on the GRETINA DAQ DSSD - 320 channels X-array – 20 channels focal plane – 20 channels

.

TS

disk

network

switch


49

X-array


50

DSSD chamber with preamps


51

ED1 tank

Delivered in September 2011Installed during the shutdown in January-February 2012


52

Faraday Cup

Ta liner Electron suppression Beam current readout

Designed, constructed, installed and tested


53

Installation


54

New quads for EMMA


5555

X-array status

All detectors working Characterization in progress

– Efficiency– Add back– stability


56

Plastic “paddles”to identify beta particles entering a Ge detector

“miniature” PM

Hamamatsu R7400U

Light guide

Ge crystal

BC-408 plastic, 3mm thick

The set of 5 which fit inside the X-array and are mounted in front of each clover.


57

X-array with plastic beta detectors

FMA

plastic

Ge

Ge

plastic

Ge


58

New high-granularity DSSD

160x160 strips64mm x 64 mm100, 140, 300, 1000 m thick


59

Preparation for high intensity beams from ATLAS

FMA– external beam dump - in progress (2012)– entrance quadrupole doublet (planned)

Focal plane detectors– large area high resolution microchannel plate detector (planned)

Implantation station– 160X160 DSSD - completed– X-array completed - completed– Plastic paddles - completed– Digital electronics - in progress (2011)

FMA Upgrades


60

FMA implantation station

Ge clovers 160X160 DSSD

Large area Si

Si/PiN box

plastic dets


61

New high-granularity DSSD

160x160 strips64mm x 64 mm100, 140, 300, 1000 m thick


62

160X160 DSSD in-beam test

ln t

E

109Te/5s

109I/100s


63

New X-array frameStephen Heimsatz

5 clover detectors in a box geometry 64x64 mm, 160x160 DSSD


64

X-array

light element studies structure of transfermium nuclei

Documents

gsiatlas user meeting

lbnlatlas user meeting

pmaatlas user meeting

isomersatlas user meeting

digital daqatlas user

n assignmentatlas user

needmore beam

lbnlsuperheavy nucleiinbeam