Publications (71)
Impact of beam far side-lobe knowledge in the presence of foregrounds for LiteBIRD
C. Leloup, G. Patanchon, J. Errard +108
We present a study of the impact of an uncertainty in the beam far side-lobe knowledge on the measurement of the Cosmic Microwave Background -mode signal at large scale. It is e…
The RoboPol Pipeline and Control System
O. G. King, D. Blinov, A. N. Ramaprakash +26
We describe the data reduction pipeline and control system for the RoboPol project. The RoboPol project is monitoring the optical -band magnitude and linear polarization of a la…
The high optical polarization in the Be/X-ray binary EXO 2030+375
P. Reig, D. Blinov, I. Papadakis +2
Polarization in classical Be stars results from Thomson scattering of the unpolarized light from the Be star in the circumstellar disc. Theory and observations agree that the maxim…
Why take the square root? An assessment of interstellar magnetic field strength estimation methods
R. Skalidis, J. Sternberg, J. R. Beattie +2
The magnetic field strength in interstellar clouds can be estimated indirectly by using the spread of dust polarization angles (). The method developed by Davis 1951 and by C…
GRB 210619B optical afterglow polarization
N. Mandarakas, D. Blinov, D. R. Aguilera-Dena +7
We report on the follow-up of the extremely bright long gamma-ray burst GRB~210619B with optical polarimetry. We conducted optopolarimetric observations of the optical afterglow of…
HI-H transition: exploring the role of the magnetic field
R. Skalidis, K. Tassis, G. V. Panopoulou +6
Atomic gas in the diffuse interstellar medium (ISM) is organized in filamentary structures. These structures usually host cold and dense molecular clumps. The Galactic magnetic fie…
The magnetic field and dust filaments in the Polaris Flare
G. V. Panopoulou, I. Psaradaki, K. Tassis
In diffuse molecular clouds, possible precursors of star-forming clouds, the effect of the magnetic field is unclear. In this work we compare the orientations of filamentary struct…
Striations in molecular clouds: Streamers or MHD waves?
A. Tritsis, K. Tassis
Dust continuum and molecular observations of the low column density parts of molecular clouds have revealed the presence of elongated structures which appear to be well aligned wit…
RoboPol: A four-channel optical imaging polarimeter
A. N. Ramaprakash, C. V. Rajarshi, H. K. Das +30
We present the design and performance of RoboPol, a four-channel optical polarimeter operating at the Skinakas Observatory in Crete, Greece. RoboPol is capable of measuring both re…
First release of LiteBIRD simulations from an end-to-end pipeline
M. Bortolami, N. Raffuzzi, L. Pagano +107
The LiteBIRD satellite mission aims at detecting Cosmic Microwave Background modes with unprecedented precision, targeting a total error on the tensor-to-scalar ratio of $Î…
RoboPol: AGN polarimetric monitoring data
D. Blinov, S. Kiehlmann, V. Pavlidou +29
We present uniformly reprocessed and re-calibrated data from the RoboPol programme of optopolarimetric monitoring of active galactic nuclei (AGN), covering observations between 201…
The RoboPol sample of optical polarimetric standards
D. Blinov, S. Maharana, F. Bouzelou +34
Optical polarimeters are typically calibrated using measurements of stars with known and stable polarization parameters. However, there is a lack of such stars available across the…
LiteBIRD Science Goals and Forecasts: Improving Sensitivity to Inflationary Gravitational Waves with Multitracer Delensing
T. Namikawa, A. I. Lonappan, C. Baccigalupi +119
We estimate the efficiency of mitigating the lensing -mode polarization, the so-called delensing, for the experiment with multiple external data sets of lensing-mass…
RoboPol: Connection between optical polarization plane rotations and gamma-ray flares in blazars
D. Blinov, V. Pavlidou, I. Papadakis +21
We use results of our 3 year polarimetric monitoring program to investigate the previously suggested connection between rotations of the polarization plane in the optical emission…
The effect of cosmic variance on the characteristics of dust polarization power spectra
V. Pelgrims, E. Ntormousi, K. Tassis
In the context of cosmic microwave background polarization studies and the characterization of the Galactic foregrounds, the power spectrum analysis of the thermal dust polarizatio…
Compelling Evidence for a Harmonic in the Light Curve of the Supermassive Black Hole Binary Candidate PKS J1309+1154
A. C. S. Readhead, M. F. Aller, A. G. Sullivan +23
We recently discovered a supermassive black hole binary (SMBHB) candidate, PKS J1309+1154, in the combined 46-yr University of Michigan Radio Astronomy Observatory (UMRAO) plus Owe…
Local alignments of parsec-scale AGN radiojets
N. Mandarakas, D. Blinov, C. Casadio +4
Context.Coherence in the characteristics of neighboring sources in 2D and 3D space may suggest the existence of large-scale cosmic structures, which are useful for cosmological stu…
Evidence for Line-of-Sight Frequency Decorrelation of Polarized Dust Emission in Data
V. Pelgrims, S. E. Clark, B. S. Hensley +5
If a single line of sight (LOS) intercepts multiple dust clouds of different spectral energy distributions and magnetic field orientations, the frequency scaling of each of the Sto…
Effect of OH depletion on measurements of the mass-to-flux ratio in molecular cloud cores
K. Tassis, K. Willacy, H. W. Yorke +1
The ratio of mass and magnetic flux determines the relative importance of magnetic and gravitational forces in the evolution of molecular clouds and their cores. Its measurement is…
RoboPol: optical polarization-plane rotations and flaring activity in blazars
D. Blinov, V. Pavlidou, I. E. Papadakis +26
We present measurements of rotations of the optical polarization of blazars during the second year of operation of RoboPol, a monitoring programme of an unbiased sample of gamma-ra…
The RoboPol optical polarization survey of gamma-ray - loud blazars
V. Pavlidou, E. Angelakis, I. Myserlis +23
We present first results from RoboPol, a novel-design optical polarimeter operating at the Skinakas Observatory in Crete. The data, taken during the May - June 2013 commissioning o…
LiteBIRD Science Goals and Forecasts. A Case Study of the Origin of Primordial Gravitational Waves using Large-Scale CMB Polarization
P. Campeti, E. Komatsu, C. Baccigalupi +107
We study the possibility of using the satellite -mode survey to constrain models of inflation producing specific features in CMB angular power spectra. We explore a p…
The Radio Spectra of High Luminosity Compact Symmetric Objects (CSO-2s): Implications for Studies of Compact Jetted Active Galactic Nuclei
P. V. de la Parra, A. C. S Readhead, T. Herbig +18
This paper addresses, for the first time, a key aspect of the phenomenology of Compact Symmetric Objects (CSOs) -- the characteristics of their radio spectra. We present a radio-sp…
Magnetic Field - Gas Density Relation and Observational Implications Revisited
A. Tritsis, G. V. Panopoulou, T. Ch. Mouschovias +2
We revisit the relation between magnetic-field strength () and gas density () for contracting interstellar clouds and fragments (or, cores), which is central in observationa…
The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium
V. Pelgrims, N. Mandarakas, R. Skalidis +21
We present the first degree-scale tomography map of the dusty magnetized interstellar medium (ISM) from stellar polarimetry and distance measurements. We used the RoboPol polarimet…
SMILE: Discriminating milli-lens systems in a VLBI pilot project
F. M. Pötzl, C. Casadio, G. Kalaitzidakis +11
Dark Matter (DM) remains poorly probed on critical, sub-galactic scales, where predictions from different models diverge in terms of abundance and density profiles of halos. Gravit…
Compact Symmetric Objects -- III Evolution of the High-Luminosity Branch and a Possible Connection with Tidal Disruption Events
A. C. S. Readhead, V. Ravi, R. D. Blandford +18
We use a sample of 54 Compact Symmetric Objects (CSOs) to confirm that there are two unrelated CSO classes: an edge-dimmed, low-luminosity class (CSO~1), and an edge-brightened, hi…
A closer look at the "characteristic" width of molecular cloud filaments
G. V. Panopoulou, I. Psaradaki, R. Skalidis +2
Filaments in Herschel molecular cloud images are found to exhibit a "characteristic width". This finding is in tension with spatial power spectra of the data, which show no indicat…
The Musca molecular cloud: The perfect "filament" is still a sheet
A. Tritsis, F. Bouzelou, R. Skalidis +3
The true 3-dimensional (3D) morphology of the Musca molecular cloud is a topic that has received significant attention lately. Given that Musca does not exhibit intense star-format…
RoboPol: First season rotations of optical polarization plane in blazars
D. Blinov, V. Pavlidou, I. Papadakis +25
We present first results on polarization swings in optical emission of blazars obtained by RoboPol, a monitoring program of an unbiased sample of gamma-ray bright blazars specially…
RoboPol: Do optical polarization rotations occur in all blazars?
D. Blinov, V. Pavlidou, I. Papadakis +23
We present a new set of optical polarization plane rotations in blazars, observed during the third year of operation of RoboPol. The entire set of rotation events discovered during…
LiteBIRD Science Goals and Forecasts: A full-sky measurement of gravitational lensing of the CMB
A. I. Lonappan, T. Namikawa, G. Piccirilli +119
We explore the capability of measuring lensing signals in full-sky polarization maps. With a arcmin beam width and an impressively low polarization noise of $2.16\,…
A Search for Supermassive Black Hole Binary Candidates in 46-Year Radio Light Curves of 83 Blazars
B. Molina, P. Mróz, P. V. De la Parra +23
The combined University of Michigan Radio Astronomy Observatory (UMRAO) and Owens Valley Radio Observatory (OVRO) blazar monitoring programs at 14.5/15 GHz provide uninterrupted li…
A Simulation Framework for the LiteBIRD Instruments
M. Tomasi, L. Pagano, A. Anand +111
LiteBIRD, the Lite (Light) satellite for the study of -mode polarization and Inflation from cosmic background Radiation Detection, is a space mission focused on primordial cosmo…
LiteBIRD Science Goals and Forecasts. Mapping the Hot Gas in the Universe
M. Remazeilles, M. Douspis, J. A. Rubiño-MartÃn +104
We assess the capabilities of the LiteBIRD mission to map the hot gas distribution in the Universe through the thermal Sunyaev-Zeldovich (SZ) effect. Our analysis relies on compreh…
PKS 2131-021 -- Discovery of Strong Coherent Sinusoidal Variations from Radio to Optical Frequencies: Compelling Evidence for a Blazar Supermassive Black Hole Binary
S. Kiehlmann, P. V. de la Parra, A. G. Sullivan +31
Haystack and Owens Valley Radio Observatory (OVRO) observations recently revealed strong, intermittent, sinusoidal total flux-density variations that maintained coherence between 1…
The LiteBIRD mission to explore cosmic inflation
T. Ghigna, A. Adler, K. Aizawa +156
LiteBIRD, the next-generation cosmic microwave background (CMB) experiment, aims for a launch in Japan's fiscal year 2032, marking a major advancement in the exploration of primord…
Compact Symmetric Objects -- I Towards a Comprehensive Bona Fide Catalog
S. Kiehlmann, M. L. Lister, A. C. S. Readhead +8
Compact Symmetric Objects (CSOs) are jetted Active Galactic Nuclei (AGN) with overall projected size <1 kpc. The classification was introduced to distinguish these objects from the…
Do Lognormal Column-Density Distributions in Molecular Clouds Imply Supersonic Turbulence?
K. Tassis, D. A. Christie, A. Urban +4
Recent observations of column densities in molecular clouds find lognormal distributions with power-law high-density tails. These results are often interpreted as indications that…
LiteBIRD Science Goals and Forecasts: constraining isotropic cosmic birefringence
E. de la Hoz, P. Diego-Palazuelos, J. Errard +112
Cosmic birefringence (CB) is the rotation of the photons' linear polarisation plane during propagation. Such an effect is a tracer of parity-violating extensions of standard electr…
A fast and robust recipe for modeling non-ideal MHD effects in star-formation simulations
E. Agianoglou, A. Tritsis, K. Tassis
Non-ideal MHD effects are thought to be a crucial component of the star-formation process. Numerically, several complications render the study of non-ideal MHD effects in 3D simula…
Polarization power spectra and dust cloud morphology
A. Konstantinou, V. Pelgrims, F. Fuchs +1
In the framework of studies of the CMB polarization and its Galactic foregrounds, the angular power spectra of thermal dust polarization maps have revealed an intriguing E/B asymme…
Filaments in the Taurus Molecular Cloud
G. V. Panopoulou, K. Tassis, P. F. Goldsmith +1
We have carried out a search for filamentary structures in the Taurus molecular cloud using line emission data from the FCRAO survey of . We have…
Requirements on the gain calibration for LiteBIRD polarisation data with blind component separation
F. Carralot, A. Carones, N. Krachmalnicoff +106
Future cosmic microwave background (CMB) experiments are primarily targeting a detection of the primordial -mode polarisation. The faintness of this signal requires exquisite co…
CARMA Large Area Star Formation Survey: Observational Analysis of Filaments in the Serpens South Molecular Cloud
M. Fernández-López, H. G. Arce, L. Looney +15
We present the N2H+(J=1-0) map of the Serpens South molecular cloud obtained as part of the CARMA Large Area Star Formation Survey (CLASSy). The observations cover 250 square arcmi…
Bright-Moon Sky as a Wide-Field Linear Polarimetric Flat Source for Calibration
S. Maharana, S. Kiehlmann, D. Blinov +20
Next-generation wide-field optical polarimeters like the Wide-Area Linear Optical Polarimeters (WALOPs) have a field of view (FoV) of tens of arcminutes. For efficient and accurate…
Compact Symmetric Objects -- II Confirmation of a Distinct Population of High-Luminosity Jetted Active Galaxies
S. Kiehlmann, A. C. S. Readhead, S. O'Neill +10
Compact Symmetric Objects (CSOs) are compact (<1 kpc), jetted Active Galactic Nuclei (AGN), whose jet axes are not aligned close to the line of sight, and whose observed emission i…
Extreme Starlight Polarization in a Region with Highly Polarized Dust Emission
G. V. Panopoulou, B. S. Hensley, R. Skalidis +2
Galactic dust emission is polarized at unexpectedly high levels, as revealed by Planck. The origin of the observed polarization fractions can be identified by charact…
SMILE: Search for MIlli-LEnses
C. Casadio, D. Blinov, A. C. S. Readhead +17
Dark Matter (DM) halos with masses below , which would help to discriminate between DM models, may be detected through their gravitational effect on distant…
Local measurements of the mean interstellar polarization at high Galactic latitudes
R. Skalidis, G. V. Panopoulou, K. Tassis +4
We conduct a small-scale pathfinding survey designed to identify the average polarization properties of the diffuse ISM locally at the lowest dust content regions. We perform deep…
CO enhancement by magnetohydrodynamic waves; Striations in the Polaris Flare
R. Skalidis, K. Gkimisi, K. Tassis +4
The formation of molecular gas in interstellar clouds is a slow process, but is enhanced by gas compression. Magnetohydrodynamic (MHD) waves create compressed quasiperiodic linear…
Starlight-polarization-based tomography of the magnetized interstellar medium: PASIPHAE's line-of-sight inversion method
V. Pelgrims, G. V. Panopoulou, K. Tassis +20
We present the first Bayesian method for tomographic decomposition of the plane-of-sky orientation of the magnetic field with the use of stellar polarimetry and distance. This stan…
Chemistry as a diagnostic of prestellar core geometry
A. Tritsis, K. Tassis, K. Willacy
We present a new method for assessing the intrinsic 3D shape of prestellar cores from molecular column densities. We have employed hydrodynamic simulations of contracting, isotherm…
What does it mean to take the mean? The effect of the averaging scale on the characterization of interstellar turbulence
A. Konstantinou, E. Ntormousi, K. Tassis
In interstellar medium studies, separating ordered and random velocity or magnetic fields is essential for interpreting turbulence in both simulations and observations. We investig…
Time evolution of the galactic relation: the impact of the magnetic field morphology
A. Konstantinou, E. Ntormousi, K. Tassis +1
One of the most frequently used indicators to characterize the magnetic field's influence on star formation is the relation between magnetic field strength and gas density (…
SOFIA/HAWC+ traces the magnetic fields in NGC 1068
E. Lopez-Rodriguez, C. D. Dowell, T. J. Jones +21
We report the first detection of galactic spiral structure by means of thermal emission from magnetically aligned dust grains. Our 89 m polarimetric imaging of NGC 1068 with th…
Zero-polarization candidate regions for calibration of wide-field optical polarimeters
N. Mandarakas, G. V. Panopoulou, V. Pelgrims +14
Context. Calibration of optical polarimeters relies on the use of stars with negligible polarization (unpolarized standard stars) for determining the instrumental polarization zero…
On the computational feasibility of Bayesian end-to-end analysis of LiteBIRD simulations within Cosmoglobe
R. Aurvik, M. Galloway, E. Gjerløw +107
We assess the computational feasibility of end-to-end Bayesian analysis of the JAXA-led LiteBIRD experiment by analysing simulated time ordered data (TOD) for a subset of detectors…
LiteBIRD Science Goals and Forecasts: Primordial Magnetic Fields
D. Paoletti, J. Rubino-Martin, M. Shiraishi +97
We present detailed forecasts for the constraints on primordial magnetic fields (PMFs) that will be obtained with the LiteBIRD satellite. The constraints are driven by the effects…
Analytic characterization of sub-Alfvénic turbulence energetics
R. Skalidis, K. Tassis, V. Pavlidou
Magnetohydrodynamic (MHD) turbulence is a cross-field process relevant to many systems. A prerequisite for understanding these systems is to constrain the role of MHD turbulence, a…
RoboPol: The optical polarization of gamma-ray--loud and gamma-ray--quiet blazars
E. Angelakis, T. Hovatta, D. Blinov +25
We present average R-band optopolarimetric data, as well as variability parameters, from the first and second RoboPol observing season. We investigate whether gamma- ray--loud and…
CARMA Large Area Star Formation Survey: Project Overview with Analysis of Dense Gas Structure and Kinematics in Barnard 1
S. Storm, L. G. Mundy, M. Fernández-López +22
We present details of the CARMA Large Area Star Formation Survey (CLASSy), while focusing on observations of Barnard 1. CLASSy is a CARMA Key Project that spectrally imaged N2H+, H…
The Magnetic Field of L1544: I. Near-Infrared Polarimetry and the Non-Uniform Envelope
Dan P. Clemens, K. Tassis, Paul F. Goldsmith
The magnetic field (B-field) of the starless dark cloud L1544 has been studied using near-infrared (NIR) background starlight polarimetry (BSP) and archival data in order to charac…
PKS~J08050111: A Second Owens Valley Radio Observatory Blazar Showing Highly Significant Sinusoidal Radio Variability -- The Tip of the Iceberg
P. V. de la Parra, S. Kiehlmann, P. Mroz +23
Owens Valley Radio Observatory (OVRO) observations of supermassive black hole binary (SMBHB) candidate PKS~2131021 revealed, for the first time, six likely characteristics of th…
Galactic Science with the LiteBIRD satellite: Spectral characterization of diffuse Galactic polarized emission at the angular power spectrum level
S. Vinzl, J. Aumont, L. Vacher +108
Detection of primordial -mode polarization in the cosmic microwave background (CMB) from tensor perturbations generated during inflation is a major scientific goal of future CMB…
Probing the cold magnetized Universe with SPICA-POL (B-BOP)
Ph. André, A. Hughes, V. Guillet +53
SPICA, the cryogenic infrared space telescope recently pre-selected for a `Phase A' concept study as one of the three remaining candidates for ESA's fifth medium class (M5) mission…
Early-time polarized optical light curve of GRB 131030A
O. G. King, D. Blinov, D. Giannios +23
We report the polarized optical light curve of a gamma-ray burst afterglow obtained using the RoboPol instrument. Observations began 655 seconds after the initial burst of gamma-ra…
Optical polarization map of the Polaris Flare with RoboPol
G. V. Panopoulou, K. Tassis, D. Blinov +26
The stages before the formation of stars in molecular clouds are poorly understood. Insights can be gained by studying the properties of quiescent clouds, such as their magnetic fi…
LiteBIRD Mission Overview after Mission Reformation
LiteBIRD Collaboration, K. Aizawa, H. Akamatsu +172
LiteBIRD is a JAXA-led space mission designed to produce all-sky microwave polarization maps. Its primary science goal is to test representative inflationary models by measuring th…
Statistical Assessment of Shapes and Magnetic Field Orientations in Molecular Clouds through Polarization Observations
K. Tassis, C. D. Dowell, R. H. Hildebrand +2
We present a novel statistical analysis aimed at deriving the intrinsic shapes and magnetic field orientations of molecular clouds using dust emission and polarization observations…
The Time-Dependent Distribution of Optical Polarization Angle Changes in Blazars
S. Kiehlmann, D. Blinov, I. Liodakis +17
At optical wavelengths, blazar Electric Vector Position Angle (EVPA) rotations linked with gamma-ray activity have been the subject of intense interest and systematic investigation…