PAN 328 (office), 624-6844
mandic @ physics.umn.edu • http://webusers.physics.umn.edu/~mandic/
Chair of the SuperCDMS Non-project R&D Working Group (2014-present); Chair of the SuperCDMS Elections and Appointments Committee (2012-present); Co-chair of the Stochastic Working Group of the LIGO Scientific Collaboration (LSC) (2006-2011); Member of the LSC-VIRGO Data Analysis Council (2007-2011); member of the LSC Data Analysis Committee (2006-2007); member of the LIGO Calibration Review Committee (2006-2013, Chair 2009-2013); McKnight Professorship (2010-2012).
My research focuses on the physics of the earliest stages of the Universe and of the highest energies. In particular, I am interested in experiments that probe content and properties of the Universe today, and that can shed light on the evolution of the Universe and on the physics at high energy scales. I work on two such experiments.
Laser Interferometer Gravitational-wave Observatory (LIGO) has built multi-kilometer interferometers at two sites: Hanford, WA and Livingston Parish, LA. These interferometers are designed to search for gravitational waves that could be produced in some of the most violent events in the Universe: mergers of two neutron stars or black holes, supernova explosions, or the Big Bang. Detection of gravitational waves would therefore open a new window into astrophysics and could potentially give us a view of the very early Universe, when the Universe was only a fraction-of-a-second old.
The gravitational wave detectors are sensitive to motions at the level of one ten-thousandth of the proton size. Much of my work is geared toward understanding and suppressing the contributions from various noise sources that are important at such sensitivities. Currently we are focusing on the seismic noise and on the Newtonian noise (fluctuations in the local gravitational field due to the motion of nearby masses). We are investigating the advantages of the underground environment in terms of these two noise sources by developing a unique 3D array of seismometers in the Homestake mine, SD. While our main motivation comes from the field of gravitational waves, this project is also of substantial interest in geophysics and is therefore conducted in collaboration with geophysicists.
My group is also involved in searches for the stochastic background of gravitational waves using LIGO data. The origin of such a background could be cosmological (early Universe models, cosmic strings models) or astrophysical (integrating supernovae or pulsar signals across the Universe). We have placed the most stringent bounds on the energy density in gravitational waves, thereby constraining some of the models of stochastic gravitational-wave background. We are pursuing searches for gravitational wave transients on the scale of minutes, hours, or longer. These searches will continue using the new, more sensitive data from Advanced LIGO, which is expected to come online in 2015.
Together with Prof. P. Cushman, I am involved in the Super Cryogenic Dark Matter Search (SuperCDMS) experiment, which is designed to search for dark matter in the form of new particles, generically called Weakly Interacting Massive Particles (WIMPs). There is an overwhelming evidence today that most of the matter in the Universe is invisible (i.e. dark), and most likely non-baryonic. However, the nature of dark matter is presently unknown, turning it into one of the most pressing problems in cosmology today. WIMPs represent one possible solution to the dark matter problem. They are particularly interesting because they naturally appear in supersymmetry and large extra-dimensions models - hence, discovery of WIMPs could have far-reaching implications for particle physics, in addition to solving the dark matter problem.
SuperCDMS has designed detectors based on crystals of germanium or silicon, operated at very low temperatures (about 50 mK), and in very low background conditions (deep underground in the Soudan mine, MN, with substantial shielding). These detectors are capable of identifying and rejecting the known particle backgrounds very efficiently, hence allowing measurement of a signal due to a new particle (WIMP). CDMS has been at the forefront of the WIMP searches over the past decade, and will remain to do so in the future, after the planned upgrade to the experiment. My research focus within CDMS is development and characterisation of detectors, mostly geared toward increasing the detector size which would simplify scaling up the total mass of the experiment. My group is also heavily involved in the analysis of CDMS data.
SuperCDMS Collaboration, Search for Low-Mass Weakly Interacting Massive Particles Using Voltage-Assisted Calorimetric Ionization Detection in the SuperCDMS Experiment, Phys. Rev. Lett. 112, 2014, 041302
S.G. Crowder, R. Namba, V. Mandic, S. Mukhoyama, and M. Peloso, Measurement of parity violation in the early universe using gravitational-wave detectors, Phys. Lett. B, 726, 2013, 66
CDMS Collaboration, Silicon detector results from the first five-tower run of CDMS II, Phys. Rev. D 88, 2013, 031104
LIGO Scientific Collaboration and Virgo Collaboration, Search for long-lived gravitational-wave transients coincident with long gamma-ray bursts, Phys. Rev. D 88, 2013, 122004
CDMS Collaboration, Silicon Detector Dark Matter Results from the Final Exposure of CDMS II, Phys. Rev. Lett. 111, 2013, 251301
C. Wu, V. Mandic, and T. Regimbau, Accessibility of the stochastic gravitational wave background from magnetars to the interferometric gravitational wave detectors, Phys. Rev. D. 87, 2013, 042002
V. Mandic, E. Thrane, S. Giampanis, and T. Regimbau, Parameter Estimation in Searches for the Stochastic Gravitational-Wave Background, Phys. Rev. Lett. 109, 2012, 171102
C. Wu, V. Mandic, and T. Regimbau, Accessibility of the gravitational-wave background due to binary coalescences to second and third generation gravitational-wave detectors, Phys. Rev. D 85, 2012, 104024
S. Ölmez, V. Mandic and X. Siemens, Anisotropies in the gravitational-wave stochastic background, J. Cosm. Astrop. Phys. 07, 2012, 009
T. Prestegard et al, Identification of noise artifacts in searches for long-duration gravitational-wave transients, Class. Quant. Grav., 29, 2012, 095018
LIGO Scientific Collaboration and Virgo Collaboration, Directional limits on gravitational waves using LIGO S5 science data, Phys. Rev. Lett. 107, 2011, 271102
E. Thrane et al, Long Gravitational-wave Transients and Associated Detection Strategies for a Network of Terrestrial Interferometers, Phys. Rev. D, 83, 2011, 083004
S. Olmez, V. Mandic, and X. Siemens, Gravitational-Wave Stochastic Background from Kinks and Cusps on Cosmic Strings, Phys. Rev. D (2010)
J. Harms et al., Characterization of the seismic environment at the Sanford Underground Laboratory, South Dakota, Class. Quant. Grav. (2010)
CDMS Collaboration, Low-threshold Analysis of CDMS Shallow-site data, Phys. Rev. D, 82, 2010, 122004
CDMS Collaboration, Dark Matter Search Results from the CDMS II Experiment, Science (2010)
LIGO Scientific Collaboration and Virgo Collaboration, An upper limit on the stochastic gravitational-wave background of cosmological origin, Nature (2009)
CDMS Collaboration, Search for Axions with the CDMS Experiment, Phys. Rev. Lett. (2009)
CDMS Collaboration, Search for Weakly Interacting Massive Particles with the First Five-Tower Data from the Cryogenic Dark Matter Search at the Soudan Underground Laboratory, Phys. Rev. Lett.
E. Thrane et al., Probing the anisotropies of a stochastic gravitational-wave background using a network of ground-based laser interferometers, Phys. Rev. D (2009)
J. Harms et al., Simulation of underground gravity gradients from stochastic seismic fields, Phys. Rev. D (2009)
LIGO Scientific Collaboration, All-sky LIGO Search for Periodic Gravitational Waves in the Early S5 Data, Phys. Rev. Lett. (2009)
LIGO Scientific Collaboration, LIGO: The Laser Interferometer Gravitational-Wave Observatory, Rep. Prog. Phys. (2009)
LIGO Scientific Collaboration, Search for Gravitational Wave Bursts from Soft Gamma Repeaters, Phys. Rev. Lett. (2008)
LIGO Scientific Collaboration, Beating the spin-down limit on gravitational wave emission from the Crab pulsar, Astrop. J. Lett. (2008)
S. Mitra et al. , Gravitational wave radiometry: Mapping a stochastic gravitational wave background, Phys. Rev. D (2008)
D. Akerib et al. , Design and Performance of a Modular Low-Radioactive Readout System for Cryogenic Detectors in the CDMS Experiment, Nucl. Inst. Meth. A (2008)
B. Abbott et al, All-sky search for periodic gravitational waves in LIGO S4 data”, Phys. Rev. (2007)
B. Abbott et al, “Upper limit map of a background of gravitational waves”,, Phys. Rev. (2007)
B. Abbott et al, “Coherent searches for periodic gravitational waves from unknown isolated sources and Scorpius X-1: results from the second LIGO science run”, Phys. Rev. (2007)
B. Abbott et al, “Searching for Stochastic Background of Gravitational Waves with LIGO”, Astrop. J (2007)
X. Siemens, V. Mandic, and J. Creighton, “Gravitational wave stochastic background from cosmic (super)strings”, Phys. Rev. Lett (2007)
LIGO Scientific Collaboration, Implications for the Origin of GRB 070201 from LIGO Observations, Astrop. J. (2008)
T. Regimbau and V. Mandic, Astrophysical sources of stochastic gravitational-wave background, Class. Quant. Grav. (2008)
X. Siemens, V. Mandic, and J. Creighton, Gravitational wave stochastic background from cosmic (super)strings, Phys. Rev. Lett. 98, 111101 (2007)
B. Abbot et al, Searching for Stochastic Background of Gravitational Waves with LIGO, Astrop. J. 659 (2007) 918
V. Mandic and A. Buonanno, Accessibility of the Pre-Big-Bang Models to LIGO, Phys. Rev. D 73, 063008 (2006)
D.S. Akerib et al, Limits on spin-dependent WIMP-nucleon interactions from the Cryogenic Dark Matter Search, Phys. Rev. D 73, 011102 (2006)
D.S. Akerib et al, Limits on spin-independent WIMP-nucleon interactions from the two-tower run of the Cryogenic Dark Matter Search, Phys. Rev. Lett. 96, 011302 (2006)
V. Mandic, B. Sadoulet, and R. Schnee, Maximum Likelihood Approach for Signal Estimation in Direct Detection Experiments for Dark Matter, Nucl. Instr. Meth. A 553, 459 (2005)
D.S. Akerib et al, Exclusion Limits on the WIMP-Nucleon Cross-Section from the First Run of the Cryogenic Dark Matter Search in the Soudan Underground Lab, Phys. Rev. D 72, 052009 (2005)
B. Abbot et al, Upper limits on a stochastic background of gravitational waves, Phys. Rev. Lett. 95 (2005) 221101
D.S. Akerib et al, First Results from the Cryogenic Dark Matter Search in the Soudan Underground Lab, Phys. Rev. Lett. 93, 211301 (2004)
D.S. Akerib et al, Exclusion limits on the WIMP-nucleon cross section from the Cryogenic Dark Matter Search, Phys. Rev. D 66, 122003 (2002)