StarBase Intensity Interferometry Update
description
Transcript of StarBase Intensity Interferometry Update
Observatorie CA HBT Workshop
StarBase Intensity Interferometry Update
D. Kieda, N. Matthews, N. Traeden,J. Skowronek
University of Utah
SII Workshop May 13, 2014
5/13/2014
Observatorie CA HBT Workshop5/13/2014
Observatorie CA HBT Workshop5/13/2014
Observatorie CA HBT Workshop5/13/2014
5/13/2014 Observatorie CA HBT Workshop
Observatorie CA HBT Workshop
Digitizer System• NI Flex-Rio digitizer Digitizer (250 Mhz sampling) & Virtex5 FPGA Front end (4
channels, 14 bit resolution (Truncate to 8 bit))
• Record to high speed 12 TB RAID system (750 Mbyte/sec)
Able to stream continuously for >6 hours
• Periodic GPS Time Stamp of FADC clock to better < 4 nsec rms
5/13/2014
5/13/2014 Observatorie CA HBT Workshop
Record all Streaming data: GPS timestamp• Post Processing (2, 3, ..N Telescope Coorrelations)• FFT Analysis• Develop/Apply Digital Filters to increase S/N
Observatorie CA HBT Workshop
Filtered PMT Spectrum
5/13/2014
DAQ System
5/13/2014 Observatorie CA HBT Workshop
PMT/APDPreamp/Fiber Optic transmitter
Pxie Bus
Virtex -5 FPGA
250 Mhz A/DConv
CPU
Streaming RAID Controller
12 TB 750 MB/Sec RAID
GPS Clock
I Gbit/sec
100 Mbyte/sec
Pxie Backplane (4 Gbit/sec)
Virtex-5 FPGA has multipleParallell-pipline FFT coresReal time data-Filtering/coorrelation?
5/13/2014 Observatorie CA HBT Workshop
Tele 1
Tele 2
Digital Filter
Digital Filter
y2
x2
x*y
Pipelined Data Analysis
This may be the only way of keeping up with the large dataflow in real time…..
Auto-correlation
Auto-correlation
Cross-correlation
Digitizer/Software Correlationtests with PMTs/Preamps
Simulated Single PMT Measured Single PMT
AutoCorrelation AutoCorrelation5/13/2014 Observatorie CA HBT Workshop
5/13/2014 Observatorie CA HBT Workshop
2 PMT Cross Correlation: Noise Pickup between adjacent PMTs -Radio Crosstalk generated by RF noise from PMTs firing-Encase in RF shielding/Use Fiber optics to sample light
4nsec
5/13/2014 Observatorie CA HBT Workshop
2 PMT Cross Correlation: Residual Correlation -Cosmic ray secondary particles striking both PMTs-Cosmic ray charged particles fluorescing in fiber optic cable
Digitizer/Software Correlation tests with PMTs/Preamps
Simulated 2-PMT Cross-correlation Measured PMT Cross-Correlation background
2G events seeded correlation = 1e-3 correlation noise < 1E-4
We should be able to measure correlation with excellent accuracy!
5/13/2014 Observatorie CA HBT Workshop
SII Lab Measurement/Hole diameters(Laser/Rotating Disk)
5/13/2014 Observatorie CA HBT Workshop
Observatorie CA HBT Workshop5/13/2014
Observatorie CA HBT Workshop5/13/2014
5/13/2014 Observatorie CA HBT Workshop
Telescope Tracking Control System:
LabView Based Servo System
Remnant of “Telescope Array 1999”
5/13/2014 Observatorie CA HBT Workshop
50
70
90
110
130
150
170
190
210
6383
2
6402
9
6422
6
6442
2
6461
9
6481
5
6501
1
6520
7
6540
3
6559
9
6579
6
6599
1
6618
8
6638
3
6658
0
6677
6
6697
3
6717
1
Time in Seconds (LST)
Azi
mut
h A
ngle
(deg
rees
)
Az Position
Az Target
50
55
60
65
70
75
80
85
90
95
6383
2
6401
8
6420
3
6438
8
6457
3
6475
8
6494
3
6512
8
6531
4
6549
8
6568
4
6586
8
6605
3
6623
8
6642
3
6660
8
6679
3
6697
9
6716
5
Time in Seconds (LST)
Elev
atio
n A
ngle
(deg
rees
)
El Position
El Target
80.2
80.25
80.3
80.35
80.4
80.45
6395
3
6395
5
6395
8
6396
0
6396
3
6396
5
6396
7
6397
0
6397
2
6397
5
6397
7
6397
9
6398
2
6398
4
6398
7
6398
9
6399
1
Time in Seconds (LST)
Elev
atio
n An
gle
(deg
rees
)
El Position
El Target
Observed tracking Performance: Alpha Lyrae Tracking
Error < 0.01°
Observatorie CA HBT Workshop5/13/2014
Observatorie CA HBT Workshop5/13/2014
Observatorie CA HBT Workshop5/13/2014
5/13/2014 Observatorie CA HBT Workshop
Star Observations (April 2014):
αLeo (Regulus): V = +1.35
ε Leo (Algenubi) V= +2.98
Single Telescope Observations
• Study Telescope tracking• Night Sky Noise• Interference noise
• Needs some further investigation, pipelined filtering?
Two Telescope Observations In Summer 2014
Test SII & Pipelined RT analysis
NSB
VSCEL cutoff
Signal
VSCEL Filter
??
Observatorie CA HBT Workshop
Observation times with the StarBase telescopes
StarBase:
For T= 15 min ( V =1 )
T= 97 min (V = 2)
StarBase Baseline: 23m
Unresolved < 1 mas (400 nm)
Examples: α Leo, β Tau or η Uma
5/13/2014
5/13/2014 Observatorie CA HBT Workshop
5/13/2014 Observatorie CA HBT Workshop
FutureTesting at StarBase Summer 2014: 2-telescope correlations
Testing at VERITAS (late 2014?)
CTA observatoryNeed to write Science Requirements, Level A/B requirementsTechnical Design review period ending (30 days)After TDR design gets frozen: Difficult to add after!
High priority: Need to form working group!
5/13/2014 Observatorie CA HBT Workshop
CTA Design QuestionsPhoto-detectors (SST, MST, LST, SCT)Telescope-to-Telescope digitization synchronization (< 2 nsec)Digitization/Storage requirementsData processing requirements
Real Time Monitoring Higher order correlations