Upload
others
View
1
Download
0
Embed Size (px)
Citation preview
TESTING DAMA/LIBRA RESULT WITH ANAIS-112 EXPERIMENT
J. Amaré, I. Coarasa, S. Cebrián, E. García, M. Martínez, M.A. Oliván, Y. Ortigoza, A. Ortiz de Solórzano, J. Puimedón, A. Salinas, M.L. Sarsa, J.A. Villar✝, P. Villar
RENATA Thematic Meeting on Dark Matter @ LSC7th February 2018
Outlin
e
• ANAIS scientific case and experiment goals• Other experiments sharing these goals • ANAIS status• Summary and outlook
• Schedule and experimental planning• Staff (recent, present and projected)• Funding requirements
• Confirmation of DAMA-LIBRA modulation signal -> same target and technique / different experimental approach / different environmental conditions affecting systematics
• At Canfranc Underground Laboratory, @ SPAIN (under 2450 m.w.e.)
• 3x3 matrix of 12.5 kg cylindrical modules = 112.5 kg of active mass
Annual modulation with NAI Scintillators
AN
AIS e
xperim
ent
at LS
C
Dark M
atter A
nnua
lMod
ulationvorbital = 30 km/s
vsun = 230 km/s
Positive identification of WIMP against backgroundscould be allowed by analyzing DM signatures, as annualmodulation in the detection rate
Small effect (<7% of S0)
Inverse modulation at verylow energies
It depends strongly on the halo model
ω=2π/365 d-1
t0 ∼1st June
Dark M
atter A
nnua
lMod
ulationvorbital = 30 km/s
vsun = 230 km/s
Positive identification of WIMP against backgroundscould be allowed by analyzing DM signatures, as annualmodulation in the detection rate
Small effect (<7% of S0)
Inverse modulation at verylow energies
It depends strongly on the halo model
ω=2π/365 d-1
t0 ∼1st June
Expe
rimen
tal S
ituation
~250kg NaI(Tl) scintillators @ LNGS
Total exposure:DAMA/NaI (100 kg NaI, 7 years, completed in 2002)+ DAMA/LIBRA (250 kg NaI, 7 cycles, + ongoing)→ total exposure: 1.33 ton x year
DAMA/LIBRA experiment
Data taking ongoing after upgrading PMTs … Results probably released soon
Expe
rimen
tal S
ituation
DAMA/LIBRA experiment
Model Independent Result
Am = 0.0112 ±0.0012 cpd/kg/keVeeT = (0.998 ±0.002 ) yT0 = (144 ±7) d (2nd June=153)No modulation above 6 keV
Evidence (9.3 σ C.L.) of an annual modulation of the single-hit events in the (2–6) keVee energy region satisfying all the requests of a DM component in the galactic halo
SI interactions From N.J. Smith at TAUP 2017, Sudbury
Expe
rimen
tal S
ituation
Expe
rimen
tal S
ituation
One single experiment has reported evidence of a signal compatible with Dark Matterobserving a model independent annual modulation
Other much sensitive experiments do not have any hint, and in fact they are reachingthe limiting NEUTRINO FLOOR -> However, comparison is model – dependent
CONTROVERSIAL issue for more than a decadeIs possible a model independent confirmation or refutation?Can DAMA/LIBRA result be a door into new Physics or just systematics?
Many WIMP scenarios considering halo and particle models have been considered and reconciling all results seems very difficult, but there is discovery potential, may be in unexpected directions
Expe
rimen
tal S
ituation
Experiments aiming at testing the DAMA LIBRA signal
NaI scintillators (same target and technique)
NaI(Tl)
CsI
KIMS @ Y2L (2013 - …)
DM-ICE @ South Pole (2011 - …)
Joint in COSINE -100 project
Taking Data from September 2016 at Yang Yang Underground Lab106 kg of NaI(Tl) from same provider / quality ANAIS’s crystalsusing a Liquid Scintillator Veto System
Expe
rimen
tal S
ituation
Experiments aiming at testing the DAMA LIBRA signal
NaI scintillators (same target and technique)
Sodium-iodide with Active Background RejectionPlanning proof-of-principle with 5 kg of NaIData taking is planned in Gran Sasso Underground Laboratory (Italy) & Stawell Underground Physics Laboratory (SUPL), in Australia
KAMLAND-PICO @ KAMIOKA
SABRE project
AN
AIS e
xperim
ent
at LS
CAnnual modulation with NAI Scintillators
• Energy threshold at or below 2 keVee• High light collection per energy unit• Effective filtering protocols for non-bulk scintillation / robust estimates of
acceptance efficiencies
• Background as low as possible below 10 keVee (at or below a few cpd/kg/keV level)
• Stability of operation and monitoring of possible systematics
AN
AIS S
tatus
• 12.5 kg cylindrical NaI(Tl) detectors built @ AS, Co (US) from NaI selected powder & developing specific radiopurity protocols
• housed in OFE copper @ AS• Mylar windows allow for LE calibration
Last three modules received at LSC in March 2017
2xHE PMT Ham12669SEL2 model coupled to each module at LSC clean room
• High Quantum Efficiency / Low dark current • Electroformed copper housing made at LSC facility• Voltage dividers made of Cuflon PCB• PMT Radioactivity screening at LSC
AN
AIS S
tatus
ANAIS-112 consists of a matrix of 3x3 modules and was installed in March 2017 after the reception of the last three AS modules
ANAIS-112 detectors testing and commissioning run started immediately and was fully operative by June-July 2017 for detector calibration and general assessment
AN
AIS S
tatus
ANAIS-112 scintillators veto system was installed in May 2017
ANAIS-112 neutron shielding was installed in July 2017. It consists of water tanks and polyethylene (40 cm)It allows partial periodic opening for calibrations
AN
AIS S
tatus
• DAQ hardware and software designed and tested with previous set-ups -> ROBUST &> SCALABLE
• Individual PMT signals digitized and fully processed• Trigger at phe level for each PMT• Logical AND coincidence in 200ns window for each module
triggering• Redundant energy conversion
• Preamplifiers designed at UZ• Electronics at air-conditioned-room to decouple from
temperature fluctuations in Hall B
AN
AIS S
tatus
Calibrations every 2 weeks at low energy
109Cd sources on flexible wires allowing the simultaneous calibration of the 9 modulesEnergies 11.9 keV, 22.6 keV and 88.0 keV
AN
AIS S
tatus
First 20 days of data taking in ANAIS-112 commissioning period
First six months of ANAIS-112DM run, from 03-08-17 until 30-01-18
159,12 days of live time accumulated
AN
AIS S
tatus
First 20 days of data taking in ANAIS-112 commissioning period
First six months of ANAIS-112DM run, from 03-08-17 until 30-01-18
159,12 days of live time accumulated
AN
AIS S
tatus
First 20 days of data taking in ANAIS-112 commissioning period
Liquid nitrogen supply shortcuts
First six months of ANAIS-112DM run, from 03-08-17 until 30-01-18
AN
AIS S
tatus
88.0 keV22.6 keV11.9 keV
Periodic 109Cd calibrations
They allow monitoring (and if necessary correcting) possible gain drifts in the modules.
Evolution of the positions of 109Cd lines along the six months of measurement.
Most of the modules have been very stable during this period of data taking.
AN
AIS S
tatus
Detector PMT/set-up Total Light Collection (phe/keV)
D0 Ham R12669 / ANAIS25Ham R12669 / ANAIS37Ham R12669 / A37D3
Ham R12669 /ANAIS112
15.6 ± 0.215.3 ± 0.115.1 ± 0.114.6± 0.1
D1 Ham R11065 / ANAIS25Ham R12669 / ANAIS25-III
Ham R12669 / ANAIS37Ham R12669 /ANAIS112
12.6 ± 0.115.2 ± 0.114.4 ± 0.114.7 ± 0.1
D2 Ham R12669 / ANAIS37Ham R12669 /ANAIS112
15.4 ± 0.114.6 ± 0.1
D3 Ham R12669 / A37D3Ham R12669 /ANAIS112
15.2 ± 0.514.6 ± 0.1
D4 Ham R12669 / A37D5Ham R12669 /ANAIS112
14 ± 114.5 ± 0.1
D5 Ham R12669 / A37D5Ham R12669 /ANAIS112
15 ± 114.3 ± 0.1
D6 Ham R12669 /ANAIS112 12.7 ± 0.1D7 Ham R12669 /ANAIS112 14.9 ± 0.1D8 Ham R12669 /ANAIS112 16.0 ± 0.1
Excellent light collection
A factor of 2 larger than thepublished light collection for
DAMA/LIBRA detectors
AN
AIS S
tatus
M.A. Oliván et al.,Astroparticle Physics 93 (2017) 86-95
Periodic monitoring of light collection along ANAIS-112 DM run.
Evolution of the light collection estimates per PMT and per module, using the periodic Cd-109 calibration (22.6 keV line) and the photoelectron area distribution derived from background runs.
It is to remark the stability of the total light collection per module along the data taking.
PMT0PMT1PMT0+PMT1
AN
AIS S
tatus
Monitoring of environmental parameters was ongoing by the start of ANAIS-112 DM run.
It consists of several windows for monitoring LN2 flux; temperatures at electronics, inner shielding, laboratory, preamplifiers, etc.; radon content in laboratory air; relative humidity; HV supply to every PMT; muon rates; etc. All the data are saved every few minutes and alarms have been set on the most relevant parameters sending an alarm message to ANAIS GLIMOS through Telegram.
AN
AIS S
tatus
Monitoring of environmental parameters was ongoing by the start of ANAIS-112 DM run.
It consists of several windows for monitoring LN2 flux; temperatures at electronics, inner shielding, laboratory, preamplifiers, etc.; radon content in laboratory air; relative humidity; HV supply to every PMT; muon rates; etc. All the data are saved every few minutes and alarms have been set on the most relevant parameters sending an alarm message to ANAIS GLIMOS through Telegram.
AN
AIS S
tatus
Monitoring of environmental parameters was ongoing by the start of ANAIS-112 DM run.
It consists of several windows for monitoring LN2 flux; temperatures at electronics, inner shielding, laboratory, preamplifiers, etc.; radon content in laboratory air; relative humidity; HV supply to every PMT; muon rates; etc. All the data are saved every few minutes and alarms have been set on the most relevant parameters sending an alarm message to ANAIS GLIMOS through Telegram.
AN
AIS S
tatus
Monitoring of environmental parameters was ongoing by the start of ANAIS-112 DM run.
It consists of several windows for monitoring LN2 flux; temperatures at electronics, inner shielding, laboratory, preamplifiers, etc.; radon content in laboratory air; relative humidity; HV supply to every PMT; muon rates; etc. All the data are saved every few minutes and alarms have been set on the most relevant parameters sending an alarm message to ANAIS GLIMOS through Telegram.
AN
AIS S
tatus
Spectra at low energy in coincidence with a high-energy gamma at 1460.5 keV (1274.5 keV) in another module for all the modules in the ANAIS-112 set-up. These spectra have been used for the determination of the potassium contents, but also for calibrating down to the threshold our experiment.
AN
AIS S
tatusWe are triggering
down to 1 keVee
PMT noise filtering:
C. Cuesta et al., EPJ C 74 (2014) 3150
Multiparametric cuts on:− Number of peaks in the pulse (n>2 in each PMT)− Temporal parameters of the pulse − Asymmetry in light sharing
Acceptance efficiency curvesfrom external calibration data
AN
AIS S
tatus
Good linearity in all the modulesA
NA
IS S
tatus
The ANAIS-112 data taken in the commissioning run up to July, 2017, have been analysed to understand the relevant background sources.Background spectra at the low energy region in ANAIS-112 commissioning run; first and latest data are compared, showing the decay of cosmogenics in the last received detectors.
First 29.2 days (March-April)
Last 30.1 days (June-July)
AN
AIS S
tatus
Preliminary background models considering the measured crystal activities and the ANAIS-112 configuration, point to equivalent relevant background sources in the very low energy region:
40K and 22Na peaks and 210Pb (bulk+surface) and 3H continua are the most significantcontributions in the very low energy region
Backgroundsources wellunderstood
AN
AIS S
tatus
J. Amaré et al.Astrop. Phys. 97
(2018) 96-105
J. Amaré et al.Eur. Phys. Journal C
76 (2016) 1-15
J. Amaré et al.JCAP02 (2015) 046
S. Cebrián et al,Astrop. Phys. 37
(2012) 60-69
(Talk by Susana Cebrián yesterday)
0.20 mBq/kg 3H
0.09 mBq/kg 3H
0.09 mBq/kg 3H
AN
AIS S
tatus
AN
AIS-112 S
ensitivity
Detection limit at 90% C.L. for a critical limit at 90% C.L. for ANAIS-112• Estimated average background from D0-D5 measured levels (corrected for cutefficiency)• 2-6 keVee region• 5 years
Dark matter hypothesisDAMA region: JCAP04(2009)10
ANAIS-112 can detect the annual modulation in the 3σ region compatible with the
DAMA/LIBRA result
90% probability of detectingan annual modulation signal at
90% C.L.
https://arxiv.org/pdf/1704.06861.pdf /
AN
AIS-112 S
ensitivity
Detection limit at 90% C.L. for a critical limit at 90% C.L. for ANAIS-112• Estimated average background from D0-D5 measured levels (corrected for cutefficiency)• 2-6 keVee region• 5 years
DAMA region: JCAP04(2009)10Model-independent annual modulation
Detection Limit for annual modulation amplitude: forANAIS-112 parameters
Factor of Merit: from the variance of the estimator of themodulated amplitude
ANAIS-112 has a detection limit forannual modulation lower than the
measured amplitude by DAMA/LIBRA: 0.0112 ± 0.0012 cpd/kg/keVee
https://arxiv.org/pdf/1704.06861.pdf /
SU
MM
AR
Y A
ND
OU
TLO
OK
ANAIS-112 has been installed successfully at LSC:112.5 kg (3x3 crystals matrix) of NaI(Tl) built at AS
-outstanding light collection-good background understanding
Electronics/Acquisition has been fine-tunedDark matter run started data taking by August, 3rd, 2017Data taking expected to go on in these conditions during the next two years
Control populations (muon-related events, blank module…) in preparationBlind annual modulation analysis foreseen after one year data taking
Good sensitivity prospects for exploring the DAMA/LIBRA signal:5 years data taking needed for a 3 sigma significant result
SU
MM
AR
Y A
ND
OU
TLO
OK
Scintillation Quenching Factor measurement for nuclear recoils: we want to investigate the possible dependence of this parameter on the crystal quality (impurities content for instance). We have three small AS crystals of different quality, and an agreement with Phil Barbeau, at Duke University, to carry out such measurements @ TUNL laboratories.
ANAIS + COSINE112.5 kg 55 kg 52 kg
Canfranc
Boulby
Yangyang
COMBINED ANALYSIS of 220 kg NaI(Tl) with present background levels
112.5 kg at Canfranc, Spain
+
107 kg at Yangyang, South Corea
Data taking of both set-ups started in 2016/17
Two years of data taking could explore the whole DAMA-LIBRA singled out parameter space
SU
MM
AR
Y A
ND
OU
TLO
OK
SU
MM
AR
Y A
ND
OU
TLO
OK
Installation of a blank module besides ANAIS-112 using similar PMTs, electronics and acquisition program in order to have a population of events without DM signal. It could be installed by spring 2018 at LSC. We are still considering this issue.
We plan to start researching the possibilities of applying Si PMs to the light readout of NaI(Tl) scintillator modules. Our present experiment is strongly limited by the rejection of PMT events down to 1 keVee, that we believe could be overcome by moving to a different light detection approach. We are considering possible collaborations.
LSV System could be faced as second phase depending on the achieved results. We are considering possible collaborations.
Making ANAIS data public after use to allow forindependent analysis
AN
AIS S
CH
ED
ULE
ANAIS schedule: Phase 1
2017 2018 2019
ANAIS-112 DM Run started on August 3rd
ANAIS-112 DM Run will end by the first week of August 2019BLIND analysis searching for modulation
R+D on application of Si PMs for the light readout of ANAIS-112 modules
ANAIS-112 DM Run first 2 years
AN
AIS S
CH
ED
ULE
ANAIS schedule: Phase 1 / Phase 2
2019 2020 2021 2022 2023
ANAIS-112 DM Run Phase 1 will continue for one year
ANAIS-112 DM Run Phase 2 will last for at least two more years
UPGRADING of ANAIS-112 detectors(still to be decided and funded)
ANAIS-112 DM Run last 2 years
AN
AIS S
TA
FF
ANAIS research team consists presently:
5 Permanent Researchers working full time in ANAIS
1 Permanent Researcher working at half time (working in T-REX)1 Permanent Researcher working at half time just incorporated by 2018, February 1st (working in CUORE)
1 Technical Engineer working at half time in ANAIS
1 PhD funded by Aragon Government Fellowship Program1 PhD to be hired by FPI program (next future)
We have lost in the last year: 1 Permanent, 1 Post-doc, and 2 Technical Positions (hired within the previous MINECO project)1 half-time Technician will be hired with the present MINECO project (next future)
No important changes are
foreseen in the next five years
AN
AIS F
UN
DIN
G
FUNDING allocated for 2018-2019: 80.000 €Project FPA-2017-83133P “Testing DAMA/LIBRA with ANAIS-112 experiment”Scarce, but we'll make for running the first two years plus some R+D on Si PMs
FUNDING required for 2020-2023: 120.000 € for running in similar conditionsAdditional funding for UPGRADING, if considered: either Si PMs light readout or Liquid Scintillator Veto System could imply an investment of about 100.000 € to be confirmed in the next two years, along the R+D phase, both the convenience of the upgrading and the funding required
FUNDING only via MINECO research project calls
Thank you for your attention