visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
장소 May 19, 2016 (Thur.) 3PM, 
일시 May 19, 2016 (Thur.) 3PM 
연사 Dr. Michael Betz, CERN 

 

The CERN Resonant WISP Search: Development, Results and Lesson-Learned

   

May 19, 2016 (Thur.) 3PM, #5318(E6-2, 5th fl.)

Dr. Michael Betz, CERN

   

Weakly Interacting Sub-eV Particles (WISPs) could reveal the composition of cold dark matter in the universe and explain a large number of astrophysical phenomena. Despite their strong theoretical motivation, these hypothetical particles could not be observed in any experiment so far.

The "CERN Resonant WISP Search"(CROWS) probes the existence of WISPs using microwave techniques.

The heart of the table-top experiment are two high-Q microwave cavity resonators. The `emitting cavity` is driven by a power amplifier at 3 GHz, resulting in the build-up of a strong electromagnetic field inside. The `receiving cavity` is placed in close vicinity and connected to a sensitive microwave receiver.

Most theories predict a weak coupling between the two cavities due to a Photon to WISP conversion process. CROWS tries to observe that coupling, while mitigating electromagnetic crosstalk with a high-end (~ 300 dB) electromagnetic shielding enclosure for the receiving part of the experiment.

Although no WISPs were detected in the most sensitive measurement-runs in 2013, a previously unexplored region in the parameter space was opened up. For `Hidden Sector Photons`, a prominent member of the WISP family, the result corresponds to an improvement in sensitivity over the previous laboratory exclusion limit by a factor of ~7.

This talk shall give a brief introduction to WISPs, the experimental search efforts worldwide and then focus on the design and development of the CROWS experiment, which happened in the framework of the authors PhD.

The encountered engineering challenges and their solutions will be highlighted. This includes the high performance EMI shielding ( 300 dB through several layers), operating electronics in strong (3 T) magnetic fields, optical signal transmission and high sensitivity (P < 1E-24 W) microwave signal detection. The operation procedure and the lessons learned during various experimental runs are shown. Furthermore, several ideas are proposed, on how to improve the experiment and its sensitivity further.

 

Contact: T.8166(CAPP Administration Office)

번호 일시 장소 연사 제목
260 Apr. 08 (Fri.), 4:00 PM  E6-2. 5st fl. #1501  Dr. Changyoung Kim, SEOUL NATIONAL UNIV.  Spectroscopic studies of iron-based superconductors : what have we learned?
259 Apr. 09 (Mon.), 11:00 AM  E6-2. 1st fl. #1323  Dr. Seung-Sup B. Lee  Doublon-holon origin of the subpeaks at the Hubbard band edges file
258 Apr. 12 (Tue.), 4 PM  E6-2. 1st fl. #1323  Dr. Jeehoon Kim, POSTECH  Confinement of Superconducting Vortices in Magnetic Force Microscopy
257 Apr. 19 (Fri.), 02:30 PM  E6-2. 1st fl. #1323  Dr. YoungWoo Nam  A family of finite-temperature electronic phase transitions in graphene multilayers file
256 Apr. 19 (Fri.), 04:00 PM  E6-2. 1st fl. #1323  Dr. Seok Kyun Son  Graphene and hBN heterostructures file
255 Apr. 19(Mon) 19:00  Zoom webinar  Chia-Ling Chien (Johns Hopkins, USA)  Evidence of Electrical Switching in Antiferromagnets and Coherent Spin Pumping file
254 Apr. 19(Tue.), 2PM  #1323(E6-2. 1st fl.)  Prof. Mark Koepke, Department of Physics and Astronomy, West Virginia University, USA  Nonlocal collisional electron transport in partially ionized plasma generation, structure, and stability
253 Apr. 2 (Fri.), 02:30 PM  Online(Zoom)  Dr. Tae Hyun Kim (SNU)  Quantum computing and entanglement generation using trapped ions and photons
252 Apr. 2 (Fri.), 04:00 PM  Online(Zoom)  Dr. Heejun Yang (KAIST)  Van der Waals heterostructures for orbital gating-based phototransistors and electronic spectroscopy
251 Apr. 27, 2017 (Thu) 4:00 pm  Seminar Room(#1323, E6-2)  Prof.Donghan Lee (Chungnam National Univ.)  반도체 양자점을 이용한 단광자 광원
250 Apr. 28 (Fri.), 02:30 PM  E6-2. 1st fl. #1323  Dr. JeongYoung Park Graduate School of EEWS, KAIST  Hot electron generation at surfaces and its impact to catalysis and renewable energy conversion
249 Apr. 28 (Fri.), 04:00 PM  #1323 (E6-2. 1st fl.)  Dr. Minkyung Jung Research Institute, DGIST  Carbon nanotubes coupled to superconducting impedance matching circuits
248 Apr. 28 (Thu.) 3PM  #2501(E6-2. 2nd fl.)  Dr. Chang Hee Sohn, SEOUL NATIONAL UNIVERSITY  Lattice/Spin/Charge Coupling in 5d Pyrochlore Cd2Os2O7
247 Apr. 5 (Tue.), 4PM  E6-2. 1st fl. #1322  Dr. Ara Go, Columbia University  A new impurity solver for multi-orbital systems: adaptive truncation of the Hilbert space
246 Apr. 9 (Fri.), 10:00 AM  Zoom webinar  Prof. Marko Loncar (Harvard University, USA)  Integrated Lithium Niobate Photonics file
245 Apr.19 (Fri.), 11:00 AM  #1323, E6-2  Dr. Ji-Sang Park  First-principles studies of semiconductors for solar cell applications file
244 April 11 (Thu.), 16:00 PM  #1323, E6-2  Prof. Joo-Hyoung Lee, GIST  Massive screening for cathode active materials using deep neural network file
243 April 11 (Wed), 1:30pm  #1323 (E6-2, 1st fl.)  Dr. Yongsoo Yang  Probing 3D Structure and Physical Properties of Materials at the Single-Atom Level file
242 April 11 (Wed), 4:00pm  #1323 (E6-2, 1st fl.)  Dr. Young-Sik Ra  Non-Gaussian states of multimode light generated via hybrid quantum information processing file
241 April 13 (Fri.), 10am  #1323 (E6-2, 1st fl.)  Dr. Sungkun Hong  Quantum meets Mechanics: from Quantum Information to Fundamental Research file