Philip Mauskopf - Academia.edu (original) (raw)

Papers by Philip Mauskopf

Research paper thumbnail of FPGA-Based TDC for Single-Photon Intensity Interferometry

Journal of Astronomical Instrumentation

A prototype intensity interferometer readout for single-photon detectors is presented as a time-t... more A prototype intensity interferometer readout for single-photon detectors is presented as a time-to-digital converter (TDC) implemented on a field-programmable gate array (FPGA). We briefly discuss the history and scientific motivations for the instrument. A comparison is drawn between the use of photomultiplier tubes in linear mode and single-photon avalanche diodes (SPAD) in Geiger mode. Different FPGA-based TDC configurations are discussed. We describe the design and implementation of a four-phase FPGA-based TDC. The paper concludes with the application of the design to investigate SPAD after-pulsing and a description of future work.

Research paper thumbnail of Maps of the Millimetre Sky from the BOOMERanG Experiment

Symposium - International Astronomical Union

In the 1998-99 flight, BOOMERanG has produced maps of ∼4% of the sky at high Galactic latitudes, ... more In the 1998-99 flight, BOOMERanG has produced maps of ∼4% of the sky at high Galactic latitudes, at frequencies of 90, 150, 240 and 410 GHz, with resolution ≳ 10'. The faint structure of the Cosmic Microwave Background at horizon and sub-horizon scales is evident in these maps. These maps compare well to the maps recently obtained at lower frequencies by the WMAP experiment. Here we compare the amplitude and morphology of the structures observed in the two sets of maps. We also outline the polarization sensitive version of BOOMERanG, which was flown early this year to measure the linear polarization of the microwave sky at 150, 240 and 350 GHz.

Research paper thumbnail of CMB Analysis of Boomerang & Maxima & the Cosmic Parameters {Ωtot,Ωbh2, Ωcdmh2, ΩΛ, ns}

Symposium - International Astronomical Union

We show how estimates of parameters characterizing inflation-based theories of structure formatio... more We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly developing cosmic microwave background (CMB) data, especially from the recent Boomerang and Maxima balloon experiments. All current CMB data plus a relatively weak prior probability on the Hubble constant, age and LSS points to little mean curvature (Ωtot = 1.08±0.06) and nearly scale invariant initial fluctuations (ns = 1.03±0.08), both predictions of (non-baroque) inflation theory. We emphasize the role that degeneracy among parameters in the Lpk = 212 ± 7 position of the (first acoustic) peak plays in defining the Ωtot range upon marginalization over other variables. Though the CDM density is in the expected range (Ωcdmh2 = 0.17 ± 0.02), the baryon density Ωbh2 = 0.030 ± 0.005 is somewhat above the independent 0.019 ± 0.002 nucleosynthesis estimates...

Research paper thumbnail of Measuring Reionization, Neutrino Mass, and Cosmic Inflation with BFORE

Journal of Low Temperature Physics

BFORE is a NASA high-altitude ultra-long-duration balloon mission proposed to measure the cosmic ... more BFORE is a NASA high-altitude ultra-long-duration balloon mission proposed to measure the cosmic microwave background (CMB) across half the sky during a 28-day mid-latitude flight launched from Wanaka, New Zealand. With the unique access to large angular scales and high frequencies provided by the balloon platform, BFORE will significantly improve measurements of the optical depth to reionization τ, breaking parameter degeneracies needed for a measurement of neutrino mass with the CMB. The large angular scale data will enable BFORE to hunt for the large-scale gravitational wave B-mode signal, as well as

Research paper thumbnail of Searching for Fossil Evidence of Agn Feedback Inwise-Selected STRIPE-82 Galaxies by Measuring the Thermal Sunyaev–Zel’Dovich Effect with the Atacama Cosmology Telescope

The Astrophysical Journal

Research paper thumbnail of The MAXIMA and MAXIPOL experiments

AIP Conference Proceedings

MAXIMA is a balloon-based bolometric experiment to measure the temperature anisotropy of the CMB ... more MAXIMA is a balloon-based bolometric experiment to measure the temperature anisotropy of the CMB over spatial frequency range 36 ≤ … ≤ 1235. The MAXIMA-1 flight produced a 124 square degree temperature anisotropy map with a beam diameter of 10 arcmin. These data have been used to produce a power spectrum which is in excellent agreement with data from BOOMERANG and DASI, but covers a wider range of angular scales. The MAXIMA power spectrum is consistent with the prediction of Λ CDM models and has been used to constrain cosmological models. The MAXIMA experiment is described and an outline is given of the contents and significance of papers written by the MAXIMA team. MAXIMA is being modified to measure the polarization anisotropy of the CMB. A brief description of this MAXIPOL experiment is also given. THE MAXIMA-1 EXPERIMENT Measurements of the anisotropy of the cosmic microwave background (CMB) can discriminate between cosmological models and determine cosmological parameters with high accuracy (Kamionkowski and Koswoski, 1999) [1]. MAXIMA is a balloon-borne experiment optimized to map the CMB anisotropy over

Research paper thumbnail of The quintessential CMB, past & future

AIP Conference Proceedings, 2001

The past, present and future of cosmic microwave background (CMB) anisotropy research is discusse... more The past, present and future of cosmic microwave background (CMB) anisotropy research is discussed, with emphasis on the Boomerang and Maxima balloon experiments. These data are combined with large scale structure (LSS) information derived from local cluster abundances and galaxy clustering and high redshift supernova (SN1) observations to explore the inflation-based cosmic structure formation paradigm. Here we primarily focus on a simplified inflation parameter set, {ω b , ω cdm , Ω tot , Ω Q , w Q , n s , τ C , σ 8 }. After marginalizing over the other cosmic and experimental variables, we find the current CMB+LSS+SN1 data gives Ω tot = 1.04±0.05, consistent with (non-baroque) inflation theory. Restricting to Ω tot = 1, we find a nearly scale invariant spectrum, n s = 1.03 ± 0.07. The CDM density, ω cdm = 0.17 ± 0.02, is in the expected range, but the baryon density, ω b ≡ Ω b h 2 = 0.030 ± 0.004, is slightly larger than the current 0.019 ± 0.002 Big Bang Nucleosynthesis estimate. Substantial dark (unclustered) energy is inferred, Ω Q ≈ 0.68 ± 0.05, and CMB+LSS Ω Q values are compatible with the independent SN1 estimates. The dark energy equation of state, parameterized by a quintessence-field pressure-to-density ratio w Q , is not well determined by CMB+LSS (w Q < −0.3 at 95% CL), but when combined with SN1 the resulting w Q < −0.7 limit is quite consistent with the w Q =−1 cosmological constant case. Though forecasts of statistical errors on parameters for current and future experiments are rosy, rooting out systematic errors will define the true progress.

Research paper thumbnail of Single-Photon Intensity Interferometry (SPIIFy): Utilizing Available Telescopes

Monthly Notices of the Royal Astronomical Society, 2017

Research paper thumbnail of BOLOCAM: A 144 Element Bolometer Array Camera for Millimeter-Wave Imaging

... Array Camera for Millimeter-Wave Imaging Philip D. Mauskopf, EyaI Gerecht and Brooks K. Rownd... more ... Array Camera for Millimeter-Wave Imaging Philip D. Mauskopf, EyaI Gerecht and Brooks K. Rownd University of Massachusetts, Amherst Samantha F. Edgington ... A white noise level of 30 ~K per1' pixel in the map was assumed and the sample variance was calculated from the ...

Research paper thumbnail of Optical requirements and modeling of coupling devices for future far-infrared space missions

Terahertz Technology and Applications III, 2010

The next generation of space missions targeting far-infrared bands will require large-format arra... more The next generation of space missions targeting far-infrared bands will require large-format arrays of extremely lownoise detectors. The development of Transition Edge Sensors (TES) array technology seems to be a viable solution for future mm-wave to Far-Infrared (FIR) space applications where low noise and high sensitivity is required. In this paper we concentrate on a key element for a high sensitivity TES detector array, that of the optical coupling between the incoming electromagnetic field and the phonon system of the suspended membrane. An intermediate solution between free space coupling and a single moded horn is where over-moded light pipes are used to concentrate energy onto multimoded absorbers. We present a comparison of modeling techniques to analyze the optical efficiency of such light pipes and their interaction with the front end optics and detector cavity.

Research paper thumbnail of Studies of atmospheric noise on Mauna Kea at 143 GHz with Bolocam

Proceedings of Spie the International Society For Optical Engineering, Jul 1, 2008

We report measurements of the fluctuations in atmospheric emission (atmospheric noise) above Maun... more We report measurements of the fluctuations in atmospheric emission (atmospheric noise) above Mauna Kea recorded with Bolocam at 143 GHz. These data were collected in November and December of 2003 with Bolocam mounted on the Caltech Submillimeter Observatory (CSO), and span approximately 40 nights. Below 0.5 Hz, the data time-streams are dominated by the f −δ atmospheric noise in all observing conditions. We were able to successfully model the atmospheric fluctuations using a Kolmogorov-Taylor turbulence model for a thin winddriven screen in approximately half of our data. Based on this modeling, we developed several algorithms to remove the atmospheric noise, and the best results were achieved when we described the fluctuations using a low-order polynomial in detector position over the 8 arcminute focal plane. However, even with these algorithms, we were not able to reach photon-background-limited instrument photometer (BLIP) performance at frequencies below 0.5 Hz in any observing conditions. Therefore, we conclude that BLIP performance is not possible from the CSO below 0.5 Hz for broadband 150 GHz receivers with subtraction of a spatial atmospheric template on scales of several arcminutes.

Research paper thumbnail of Transition Edge Superconducting detector arrays for a 40-200 pm spectrometer on the SPICA telescope

Research paper thumbnail of Cosmic Microwave Background

Research paper thumbnail of MBI: Millimetre-wave bolometric interferometer

AIP Conference Proceedings, 2002

We present the design of the prototype of a millimetre-wave bolometeric interferometer (MBI). Thi... more We present the design of the prototype of a millimetre-wave bolometeric interferometer (MBI). This interferometer uses two arrays bolometers as detectors. The combination of high sensitivity bolometers and interferometric imaging appears to be well suited for precision measurements in observational cosmology.

Research paper thumbnail of First results from the BOOMERanG experiment

AIP Conference Proceedings, 2001

We report the first results from the BOOMERanG experiment, which mapped at 90, 150, 240 and 410 G... more We report the first results from the BOOMERanG experiment, which mapped at 90, 150, 240 and 410 GHz a wide (3%) region of the microwave sky with minimal local contamination. From the data of the best 150 GHz detector we find evidence for a well defined peak in the power spectrum of temperature fluctuations of the Cosmic Microwave Background, localized at = 197 ± 6, with an amplitude of (68 ± 8)µK CMB. The location, width and amplitude of the peak is suggestive of acoustic oscillations in the primeval plasma. In the framework of inflationary adiabatic cosmological models the measured spectrum allows a Bayesian estimate of the curvature of the Universe and of other cosmological parameters. With reasonable priors we find Ω = (1.07 ± 0.06) and n s = (1.00 ± 0.08) (68%C.L.) in excellent agreement with the expectations from the simplest inflationary theories. We also discuss the limits on the density of baryons, of cold dark matter and on the cosmological constant.

Research paper thumbnail of Interstellar dust in the BOOMERanG maps

AIP Conference Proceedings, 2002

Interstellar dust (ISD) emission is present in the mm-wave maps obtained by the BOOMERanG experim... more Interstellar dust (ISD) emission is present in the mm-wave maps obtained by the BOOMERanG experiment at intermediate and high Galactic latitudes. We find that, while being subdominant at the lower frequencies (90,150, 240 GHz), thermal emission from ISD is dominant at 410 GHz, and is well correlated with the IRAS map at 100 um. We find also that the angular power spectrum of ISD fluctuations at 410 GHz is a power law, and its level is negligible with respect to the angular power spectrum of the Cosmic Microwave Background (CMB) at 90 and 150 GHz.

Research paper thumbnail of Development of Lumped Element Kinetic Inductance Detectors for the W-Band

Journal of Low Temperature Physics, 2016

We are developing a Lumped Element Kinetic Inductance Detector (LEKID) array able to operate in t... more We are developing a Lumped Element Kinetic Inductance Detector (LEKID) array able to operate in the W-band (75−110 GHz) in order to perform ground-based Cosmic Microwave Background (CMB) and mm-wave astronomical observations. The W-band is close to optimal in terms of contamination of the CMB from Galactic synchrotron, free-free, and thermal interstellar dust. In this band, the atmosphere has very good transparency, allowing interesting groundbased observations with large (>30 m) telescopes, achieving high angular resolution (<0.4 arcmin). In this work we describe the startup measurements devoted to the optimization of a W-band camera/spectrometer prototype for large aperture telescopes like the 64 m SRT (Sardinia Radio Telescope). In the process of selecting the best superconducting film for the LEKID, we characterized a 40 nm thick Aluminum 2-pixel array. We measured the minimum frequency able to break CPs (i.e. hν = 2∆ (T c) = 3.5k B T c) obtaining ν = 95.5 GHz, that corresponds to a critical temperature of 1.31 K. This is not suitable to cover the entire W-band. For an 80 nm layer the minimum frequency decreases to 93.2 GHz, which corresponds to a critical temperature of 1.28 K; this value is still suboptimal for W-band operation. Further increase of the Al film thickness results in bad performance of the detector. We have thus considered a Titanium-Aluminum bi-layer (10 nm thick Ti + 25 nm thick Al, already tested in other laboratories [1]), for which we measured a critical temperature of 820 mK and a cut-on frequency of 65 GHz: so this solution allows operation in the entire W-band.

Research paper thumbnail of A comparison of radome- and astrodome-enclosed large radio telescopes at millimeter wavelengths: The Large Millimeter Telescope

Research paper thumbnail of Performance of Planar Ortho-Mode Transducers for CMB Satellite Missions

Twenty First International Symposium on Space Terahertz Technology, Mar 1, 2010

Planar waveguide E-field probes have been used in a number of millimeter wave instruments althoug... more Planar waveguide E-field probes have been used in a number of millimeter wave instruments although usually for single polarization detection in rectangular waveguide. The coupling efficiency of these types of probes is found to be high over the full waveguide bandwidth. Because ...

Research paper thumbnail of Cooling Bolocam, A New Camera for the Future GTM/LMT

The observations at millimeter wavelength begin to occupy an important role in the modern astrono... more The observations at millimeter wavelength begin to occupy an important role in the modern astronomy. The fast growing up of millimeter--wave bolometer array systems, such as SCUBA on the JCMT, MPfIR on the IRAM telescope or SuZIE on the CSO, have opened a new window that have allowed astronomers to make significant contributions in such diverse fields as the study

Research paper thumbnail of FPGA-Based TDC for Single-Photon Intensity Interferometry

Journal of Astronomical Instrumentation

A prototype intensity interferometer readout for single-photon detectors is presented as a time-t... more A prototype intensity interferometer readout for single-photon detectors is presented as a time-to-digital converter (TDC) implemented on a field-programmable gate array (FPGA). We briefly discuss the history and scientific motivations for the instrument. A comparison is drawn between the use of photomultiplier tubes in linear mode and single-photon avalanche diodes (SPAD) in Geiger mode. Different FPGA-based TDC configurations are discussed. We describe the design and implementation of a four-phase FPGA-based TDC. The paper concludes with the application of the design to investigate SPAD after-pulsing and a description of future work.

Research paper thumbnail of Maps of the Millimetre Sky from the BOOMERanG Experiment

Symposium - International Astronomical Union

In the 1998-99 flight, BOOMERanG has produced maps of ∼4% of the sky at high Galactic latitudes, ... more In the 1998-99 flight, BOOMERanG has produced maps of ∼4% of the sky at high Galactic latitudes, at frequencies of 90, 150, 240 and 410 GHz, with resolution ≳ 10'. The faint structure of the Cosmic Microwave Background at horizon and sub-horizon scales is evident in these maps. These maps compare well to the maps recently obtained at lower frequencies by the WMAP experiment. Here we compare the amplitude and morphology of the structures observed in the two sets of maps. We also outline the polarization sensitive version of BOOMERanG, which was flown early this year to measure the linear polarization of the microwave sky at 150, 240 and 350 GHz.

Research paper thumbnail of CMB Analysis of Boomerang & Maxima & the Cosmic Parameters {Ωtot,Ωbh2, Ωcdmh2, ΩΛ, ns}

Symposium - International Astronomical Union

We show how estimates of parameters characterizing inflation-based theories of structure formatio... more We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly developing cosmic microwave background (CMB) data, especially from the recent Boomerang and Maxima balloon experiments. All current CMB data plus a relatively weak prior probability on the Hubble constant, age and LSS points to little mean curvature (Ωtot = 1.08±0.06) and nearly scale invariant initial fluctuations (ns = 1.03±0.08), both predictions of (non-baroque) inflation theory. We emphasize the role that degeneracy among parameters in the Lpk = 212 ± 7 position of the (first acoustic) peak plays in defining the Ωtot range upon marginalization over other variables. Though the CDM density is in the expected range (Ωcdmh2 = 0.17 ± 0.02), the baryon density Ωbh2 = 0.030 ± 0.005 is somewhat above the independent 0.019 ± 0.002 nucleosynthesis estimates...

Research paper thumbnail of Measuring Reionization, Neutrino Mass, and Cosmic Inflation with BFORE

Journal of Low Temperature Physics

BFORE is a NASA high-altitude ultra-long-duration balloon mission proposed to measure the cosmic ... more BFORE is a NASA high-altitude ultra-long-duration balloon mission proposed to measure the cosmic microwave background (CMB) across half the sky during a 28-day mid-latitude flight launched from Wanaka, New Zealand. With the unique access to large angular scales and high frequencies provided by the balloon platform, BFORE will significantly improve measurements of the optical depth to reionization τ, breaking parameter degeneracies needed for a measurement of neutrino mass with the CMB. The large angular scale data will enable BFORE to hunt for the large-scale gravitational wave B-mode signal, as well as

Research paper thumbnail of Searching for Fossil Evidence of Agn Feedback Inwise-Selected STRIPE-82 Galaxies by Measuring the Thermal Sunyaev–Zel’Dovich Effect with the Atacama Cosmology Telescope

The Astrophysical Journal

Research paper thumbnail of The MAXIMA and MAXIPOL experiments

AIP Conference Proceedings

MAXIMA is a balloon-based bolometric experiment to measure the temperature anisotropy of the CMB ... more MAXIMA is a balloon-based bolometric experiment to measure the temperature anisotropy of the CMB over spatial frequency range 36 ≤ … ≤ 1235. The MAXIMA-1 flight produced a 124 square degree temperature anisotropy map with a beam diameter of 10 arcmin. These data have been used to produce a power spectrum which is in excellent agreement with data from BOOMERANG and DASI, but covers a wider range of angular scales. The MAXIMA power spectrum is consistent with the prediction of Λ CDM models and has been used to constrain cosmological models. The MAXIMA experiment is described and an outline is given of the contents and significance of papers written by the MAXIMA team. MAXIMA is being modified to measure the polarization anisotropy of the CMB. A brief description of this MAXIPOL experiment is also given. THE MAXIMA-1 EXPERIMENT Measurements of the anisotropy of the cosmic microwave background (CMB) can discriminate between cosmological models and determine cosmological parameters with high accuracy (Kamionkowski and Koswoski, 1999) [1]. MAXIMA is a balloon-borne experiment optimized to map the CMB anisotropy over

Research paper thumbnail of The quintessential CMB, past & future

AIP Conference Proceedings, 2001

The past, present and future of cosmic microwave background (CMB) anisotropy research is discusse... more The past, present and future of cosmic microwave background (CMB) anisotropy research is discussed, with emphasis on the Boomerang and Maxima balloon experiments. These data are combined with large scale structure (LSS) information derived from local cluster abundances and galaxy clustering and high redshift supernova (SN1) observations to explore the inflation-based cosmic structure formation paradigm. Here we primarily focus on a simplified inflation parameter set, {ω b , ω cdm , Ω tot , Ω Q , w Q , n s , τ C , σ 8 }. After marginalizing over the other cosmic and experimental variables, we find the current CMB+LSS+SN1 data gives Ω tot = 1.04±0.05, consistent with (non-baroque) inflation theory. Restricting to Ω tot = 1, we find a nearly scale invariant spectrum, n s = 1.03 ± 0.07. The CDM density, ω cdm = 0.17 ± 0.02, is in the expected range, but the baryon density, ω b ≡ Ω b h 2 = 0.030 ± 0.004, is slightly larger than the current 0.019 ± 0.002 Big Bang Nucleosynthesis estimate. Substantial dark (unclustered) energy is inferred, Ω Q ≈ 0.68 ± 0.05, and CMB+LSS Ω Q values are compatible with the independent SN1 estimates. The dark energy equation of state, parameterized by a quintessence-field pressure-to-density ratio w Q , is not well determined by CMB+LSS (w Q < −0.3 at 95% CL), but when combined with SN1 the resulting w Q < −0.7 limit is quite consistent with the w Q =−1 cosmological constant case. Though forecasts of statistical errors on parameters for current and future experiments are rosy, rooting out systematic errors will define the true progress.

Research paper thumbnail of Single-Photon Intensity Interferometry (SPIIFy): Utilizing Available Telescopes

Monthly Notices of the Royal Astronomical Society, 2017

Research paper thumbnail of BOLOCAM: A 144 Element Bolometer Array Camera for Millimeter-Wave Imaging

... Array Camera for Millimeter-Wave Imaging Philip D. Mauskopf, EyaI Gerecht and Brooks K. Rownd... more ... Array Camera for Millimeter-Wave Imaging Philip D. Mauskopf, EyaI Gerecht and Brooks K. Rownd University of Massachusetts, Amherst Samantha F. Edgington ... A white noise level of 30 ~K per1' pixel in the map was assumed and the sample variance was calculated from the ...

Research paper thumbnail of Optical requirements and modeling of coupling devices for future far-infrared space missions

Terahertz Technology and Applications III, 2010

The next generation of space missions targeting far-infrared bands will require large-format arra... more The next generation of space missions targeting far-infrared bands will require large-format arrays of extremely lownoise detectors. The development of Transition Edge Sensors (TES) array technology seems to be a viable solution for future mm-wave to Far-Infrared (FIR) space applications where low noise and high sensitivity is required. In this paper we concentrate on a key element for a high sensitivity TES detector array, that of the optical coupling between the incoming electromagnetic field and the phonon system of the suspended membrane. An intermediate solution between free space coupling and a single moded horn is where over-moded light pipes are used to concentrate energy onto multimoded absorbers. We present a comparison of modeling techniques to analyze the optical efficiency of such light pipes and their interaction with the front end optics and detector cavity.

Research paper thumbnail of Studies of atmospheric noise on Mauna Kea at 143 GHz with Bolocam

Proceedings of Spie the International Society For Optical Engineering, Jul 1, 2008

We report measurements of the fluctuations in atmospheric emission (atmospheric noise) above Maun... more We report measurements of the fluctuations in atmospheric emission (atmospheric noise) above Mauna Kea recorded with Bolocam at 143 GHz. These data were collected in November and December of 2003 with Bolocam mounted on the Caltech Submillimeter Observatory (CSO), and span approximately 40 nights. Below 0.5 Hz, the data time-streams are dominated by the f −δ atmospheric noise in all observing conditions. We were able to successfully model the atmospheric fluctuations using a Kolmogorov-Taylor turbulence model for a thin winddriven screen in approximately half of our data. Based on this modeling, we developed several algorithms to remove the atmospheric noise, and the best results were achieved when we described the fluctuations using a low-order polynomial in detector position over the 8 arcminute focal plane. However, even with these algorithms, we were not able to reach photon-background-limited instrument photometer (BLIP) performance at frequencies below 0.5 Hz in any observing conditions. Therefore, we conclude that BLIP performance is not possible from the CSO below 0.5 Hz for broadband 150 GHz receivers with subtraction of a spatial atmospheric template on scales of several arcminutes.

Research paper thumbnail of Transition Edge Superconducting detector arrays for a 40-200 pm spectrometer on the SPICA telescope

Research paper thumbnail of Cosmic Microwave Background

Research paper thumbnail of MBI: Millimetre-wave bolometric interferometer

AIP Conference Proceedings, 2002

We present the design of the prototype of a millimetre-wave bolometeric interferometer (MBI). Thi... more We present the design of the prototype of a millimetre-wave bolometeric interferometer (MBI). This interferometer uses two arrays bolometers as detectors. The combination of high sensitivity bolometers and interferometric imaging appears to be well suited for precision measurements in observational cosmology.

Research paper thumbnail of First results from the BOOMERanG experiment

AIP Conference Proceedings, 2001

We report the first results from the BOOMERanG experiment, which mapped at 90, 150, 240 and 410 G... more We report the first results from the BOOMERanG experiment, which mapped at 90, 150, 240 and 410 GHz a wide (3%) region of the microwave sky with minimal local contamination. From the data of the best 150 GHz detector we find evidence for a well defined peak in the power spectrum of temperature fluctuations of the Cosmic Microwave Background, localized at = 197 ± 6, with an amplitude of (68 ± 8)µK CMB. The location, width and amplitude of the peak is suggestive of acoustic oscillations in the primeval plasma. In the framework of inflationary adiabatic cosmological models the measured spectrum allows a Bayesian estimate of the curvature of the Universe and of other cosmological parameters. With reasonable priors we find Ω = (1.07 ± 0.06) and n s = (1.00 ± 0.08) (68%C.L.) in excellent agreement with the expectations from the simplest inflationary theories. We also discuss the limits on the density of baryons, of cold dark matter and on the cosmological constant.

Research paper thumbnail of Interstellar dust in the BOOMERanG maps

AIP Conference Proceedings, 2002

Interstellar dust (ISD) emission is present in the mm-wave maps obtained by the BOOMERanG experim... more Interstellar dust (ISD) emission is present in the mm-wave maps obtained by the BOOMERanG experiment at intermediate and high Galactic latitudes. We find that, while being subdominant at the lower frequencies (90,150, 240 GHz), thermal emission from ISD is dominant at 410 GHz, and is well correlated with the IRAS map at 100 um. We find also that the angular power spectrum of ISD fluctuations at 410 GHz is a power law, and its level is negligible with respect to the angular power spectrum of the Cosmic Microwave Background (CMB) at 90 and 150 GHz.

Research paper thumbnail of Development of Lumped Element Kinetic Inductance Detectors for the W-Band

Journal of Low Temperature Physics, 2016

We are developing a Lumped Element Kinetic Inductance Detector (LEKID) array able to operate in t... more We are developing a Lumped Element Kinetic Inductance Detector (LEKID) array able to operate in the W-band (75−110 GHz) in order to perform ground-based Cosmic Microwave Background (CMB) and mm-wave astronomical observations. The W-band is close to optimal in terms of contamination of the CMB from Galactic synchrotron, free-free, and thermal interstellar dust. In this band, the atmosphere has very good transparency, allowing interesting groundbased observations with large (>30 m) telescopes, achieving high angular resolution (<0.4 arcmin). In this work we describe the startup measurements devoted to the optimization of a W-band camera/spectrometer prototype for large aperture telescopes like the 64 m SRT (Sardinia Radio Telescope). In the process of selecting the best superconducting film for the LEKID, we characterized a 40 nm thick Aluminum 2-pixel array. We measured the minimum frequency able to break CPs (i.e. hν = 2∆ (T c) = 3.5k B T c) obtaining ν = 95.5 GHz, that corresponds to a critical temperature of 1.31 K. This is not suitable to cover the entire W-band. For an 80 nm layer the minimum frequency decreases to 93.2 GHz, which corresponds to a critical temperature of 1.28 K; this value is still suboptimal for W-band operation. Further increase of the Al film thickness results in bad performance of the detector. We have thus considered a Titanium-Aluminum bi-layer (10 nm thick Ti + 25 nm thick Al, already tested in other laboratories [1]), for which we measured a critical temperature of 820 mK and a cut-on frequency of 65 GHz: so this solution allows operation in the entire W-band.

Research paper thumbnail of A comparison of radome- and astrodome-enclosed large radio telescopes at millimeter wavelengths: The Large Millimeter Telescope

Research paper thumbnail of Performance of Planar Ortho-Mode Transducers for CMB Satellite Missions

Twenty First International Symposium on Space Terahertz Technology, Mar 1, 2010

Planar waveguide E-field probes have been used in a number of millimeter wave instruments althoug... more Planar waveguide E-field probes have been used in a number of millimeter wave instruments although usually for single polarization detection in rectangular waveguide. The coupling efficiency of these types of probes is found to be high over the full waveguide bandwidth. Because ...

Research paper thumbnail of Cooling Bolocam, A New Camera for the Future GTM/LMT

The observations at millimeter wavelength begin to occupy an important role in the modern astrono... more The observations at millimeter wavelength begin to occupy an important role in the modern astronomy. The fast growing up of millimeter--wave bolometer array systems, such as SCUBA on the JCMT, MPfIR on the IRAM telescope or SuZIE on the CSO, have opened a new window that have allowed astronomers to make significant contributions in such diverse fields as the study