APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.
-
Upload
gary-scott -
Category
Documents
-
view
218 -
download
0
description
Transcript of APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.
![Page 1: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/1.jpg)
APS April2000APS April2000MeetingMeeting
Ahmet Sedat AyanDept. of Physics & Astronomy
University of Iowa
![Page 2: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/2.jpg)
Why HF?Why HF?
Covers the pseudorapidity range 3-5 HF psedorapidity range 4.5-5 will get
100Mrad/year. Therefore the detector should be able to withstand this exceptionally high radiation field.
Two main objectives :1. To improve the measurement of the missing
transverse energy EmissT
2. To enable identification and reconstruction of very forward jets
![Page 3: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/3.jpg)
CMS Longitudinal ViewCMS Longitudinal View
![Page 4: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/4.jpg)
HFHF
Calibration
Readout Boxes
Photo detectors
Transporter
FE, Trig/DAQDCS, Voltage
Shielding
Absorber
OpticsQuartz Fibers
![Page 5: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/5.jpg)
HF Transverse HF Transverse SegmentationSegmentation
QQ/QP Border
3 < < 5HF is segmented in = = 0.175
EM (31/20-deg)HAD (25/20-deg)TC(13/20-deg)TOTAL(69/20-deg)
The active region extends from r=12.5 cm to 130 cm.The depth is 165 cm (Fe).
![Page 6: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/6.jpg)
Experimental TechniqueExperimental Technique
•Light is generated by Cherenkov effect in quartz fibers•Sensitive to relativistic charged particles (Compton electrons...)
•d2N/dxdl=2paz2(sin2q/l2)• =(2paz2/ l2 )[1-1/b2n2]• bmin = 1/n• Emin ~ 200 keV
•Amount of collected light depends on the angle between the particle path and the fiber axis
![Page 7: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/7.jpg)
HF PPP1 Side ViewHF PPP1 Side View
Fiber Bundles(EM, HAD and
TC)300-micron core
QP
Ferrules
ROBox( Light Guides)
R6425 PMTs
Iron Absorbe
r(9.5 lI)
Radioactive Source
Tubes
3 x 3 Tower structure
(6 cm x 6 cm)
LED, Laser and PIN
PDs
![Page 8: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/8.jpg)
2.5 mm
2.5 mm
TC (30 cm)HAD (143 cm)
EM (165 cm)
HF Longitudinal HF Longitudinal SegmentationSegmentation
EM HAD
TC
![Page 9: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/9.jpg)
Uniformity Scan with Uniformity Scan with ElectronsElectrons
•There is a +/- 6 % response nonuniformity to electrons due to fiber periodicity at every 2.5 mm (5 mm for EM).
![Page 10: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/10.jpg)
Response to Electrons Response to Electrons and Pionsand Pions
•HF PPP1 responds linearly within 1% to electrons in the energy range tested (6 – 200 GeV). The pion (neg) response is highly nonlinear.
![Page 11: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/11.jpg)
Electromagnetic Energy Electromagnetic Energy ResolutionResolution
Electromagnetic energy resolution is completely dominated by photostatistics (Np.e.). The usual parametrization, a/sqrt(E) + b, results in a~192% and b~9% for the PPP1. 0.85% fiber fraction degrades the EM energy resolution by a ~sqrt(2) compared to HAD95 (1.6%).
137%/sqrt(E) with 1.6% fiber packingFraction (HAD95)
![Page 12: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/12.jpg)
Hadronic Energy Hadronic Energy ResolutionResolution
Hadronic energy resolution is dominated by non-stochastic processes at higher energies. Photo statistics becomes important only at lower energies. The intrinsic energy resolution can be expressed as c-d*ln(E). The expected energy resolution at 1 TeV is 18%.
![Page 13: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/13.jpg)
FLUKAFLUKA CalculationsCalculations
Recent radiation background simulations show improvement in the design of the shielding around the PMT region by a factor of ~two. There is no issue with the radiation dose or neutron flux where the PMTs are located.
All neutrons 2.54x1012
Neutrons (E>100KeV) 1.63x1012
Neutrons (E>20 MeV) 5.12x1011 Ch. Hadrons 2.26x1010
Muons 4.65x109
Photons 1.53x1012
Dose 7 krad
![Page 14: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/14.jpg)
OpticsOptics: FiberFiber RadiationRadiation DamageDamage
Several quartz fiber irradiation studies have been carried out in the last several years. The induced attenuation profile shows that there is less absorbtion in 400-500 nm (PMT) region compared to either shorter or longer wavelengths.
~200 MRad
63% loss
![Page 15: APS April2000 Meeting Ahmet Sedat Ayan Dept. of Physics Astronomy University of Iowa.](https://reader035.fdocuments.us/reader035/viewer/2022062401/5a4d1b6f7f8b9ab0599b4e4d/html5/thumbnails/15.jpg)
PPP-I SummaryPPP-I Summary
1% linearity in response to electrons. Highly non-linear to negative pions
Electromagnetic Energy Resolution: 192% 9% Expected Hadronic Energy Resolution at 1TeV is 18% +/- 6% non-uniformity in response to electrons due to fiber
periodicity Suppressed induced radiation damage on fibers in PMT region (400-500nm)