Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season.

We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220 GHz dataset. The Q/U maps now reach depths of 2.8, 2.8, and 8.8 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈600 square degrees at 95 GHz and ≈400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.009. These are the strongest constraints to date on primordial gravitational waves.

Constraints on Primordial Gravitational Waves Using Planck, WMAP, and New BICEP2/Keck Observations through the 2015 Season.

We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 and 150 GHz. The Q and U maps reach depths of 5.2, 2.9, and 26 µK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈400 square degrees. The 220 GHz maps achieve a signal to noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto and cross spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.07 at 95% confidence, which tightens to r_{0.05}<0.06 in conjunction with Planck temperature measurements and other data. The lensing signal is detected at 8.8σ significance. Running a maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.020. These are the strongest constraints to date on primordial gravitational waves.

Improved Constraints on Cosmology and Foregrounds from BICEP2 and Keck Array Cosmic Microwave Background Data with Inclusion of 95 GHz Band.

We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.

Detection of B-mode polarization at degree angular scales by BICEP2.

We report results from the BICEP2 experiment, a cosmic microwave background (CMB) polarimeter specifically designed to search for the signal of inflationary gravitational waves in the B-mode power spectrum around ℓ∼80. The telescope comprised a 26 cm aperture all-cold refracting optical system equipped with a focal plane of 512 antenna coupled transition edge sensor 150 GHz bolometers each with temperature sensitivity of ≈300 µK(CMB)√s. BICEP2 observed from the South Pole for three seasons from 2010 to 2012. A low-foreground region of sky with an effective area of 380 square deg was observed to a depth of 87 nK deg in Stokes Q and U. In this paper we describe the observations, data reduction, maps, simulations, and results. We find an excess of B-mode power over the base lensed-ΛCDM expectation in the range 30 < ℓ < 150, inconsistent with the null hypothesis at a significance of >5σ. Through jackknife tests and simulations based on detailed calibration measurements we show that systematic contamination is much smaller than the observed excess. Cross correlating against WMAP 23 GHz maps we find that Galactic synchrotron makes a negligible contribution to the observed signal. We also examine a number of available models of polarized dust emission and find that at their default parameter values they predict power ∼(5-10)× smaller than the observed excess signal (with no significant cross-correlation with our maps). However, these models are not sufficiently constrained by external public data to exclude the possibility of dust emission bright enough to explain the entire excess signal. Cross correlating BICEP2 against 100 GHz maps from the BICEP1 experiment, the excess signal is confirmed with 3σ significance and its spectral index is found to be consistent with that of the CMB, disfavoring dust at 1.7σ. The observed B-mode power spectrum is well fit by a lensed-ΛCDM+tensor theoretical model with tensor-to-scalar ratio r = 0.20_(-0.05)(+0.07), with r = 0 disfavored at 7.0σ. Accounting for the contribution of foreground, dust will shift this value downward by an amount which will be better constrained with upcoming data sets.

Prevalence and profile of sleep disturbances in Guillain-Barre Syndrome: a prospective questionnaire-based study during 10 days of hospitalization.

INTRODUCTION: Sleep disturbances in Guillain-Barre Syndrome (GBS), though common, have not received focused attention. OBJECTIVES: To study frequency and nature of sleep disturbances in patients with GBS, using validated questionnaires, and analyze the contributing factors. MATERIALS AND METHODS: This prospective study included 60 patients fulfilling National Institute of Neurological and Communicative Diseases and Stroke (NINCDS) criteria for GBS (mean age: 32.7 ± 12.9 years; median: 30 years; M:F = 46:14), evaluated from 2008 to 2010. Data regarding sleep were collected on 10 consecutive days following admission using Richard Campbell Sleep score, St Mary's Hospital Sleep Questionnaire, and Pittsburgh Sleep Quality Index (PSQI) and correlated with various possible contributing factors like pain, paresthesia, anxiety, depression, autonomic dysfunctions, severity of disease, and therapeutic interventions among others. OBSERVATIONS: Qualitative and quantitative sleep disturbances were rather frequent and involved over 50% patients: abnormal PSQI - 13.3%, abnormal score on Richard scale - 51.6%, abnormal sleep onset latency - 35%, sleep fragmentation - 40%, and reduced sleep duration - 46.6%. The symptoms were severe during the first week of hospitalization and reduced thereafter. Sleep disturbances as scored on Richard scale significantly correlated with anxiety, pain, paresthesia, and severity of immobility (P < 0.05) but not with depression and use of analgesics or antineuritic drugs. CONCLUSIONS: This study first of its kind suggests that sleep disturbance in GBS is frequent, multi-factorial, often disturbing, and varies during the course of illness. Routine enquiry into the sleep disturbances and timely intervention may reduce morbidity and improve their quality of life.

Temporal profile of pain and other sensory manifestations in Guillain-Barre' syndrome during ten days of hospitalization.

BACKGROUND: Focused studies on sensory manifestations, especially pain and paresthesia in Guillain-Barre' (GB) syndrome are few and far between. AIM: To study the sensory manifestations in GB syndrome during 10 days of hospitalization with clinico-electrophysiological correlation. MATERIALS AND METHODS: The study included 60 non-consecutive patients with GB syndrome, fulfilling National Institute of Neurological and Communicative Disorders and Stroke (NINCDS) criteria for GB syndrome. Data especially related to clinical and electrophysiological evidence of sensory involvement were analyzed. Pain was assessed using a) visual analogue paraesthesias (Vapar), b) visual analogue for pain (Vap) and c) verbal rating scale for pain (Verp). RESULTS: Sensory symptoms were widely prevalent: paraesthesia in 45 (75%) patients and pain in 30 (50%) patients. Impairment of different sensory modalities included: pain in 8 (13.3%), joint position sense in 14 (23.3%), and vibration in 11 (18.3%). Electrophysiological evidence of abnormal sensory nerve conduction was noted in 35 (58.3%) patients. Pain assessment using Vapar, Vap and Verp for from Day 1 to Day 10 of hospitalization revealed that from Day 7 onwards the degree and frequency of sensory symptoms and signs decreased. On comparing various clinico-electrophysiological parameters among patients of GB syndrome with and without pain and paresthesia. Presence of respiratory distress correlated with pain and paresthesia (P=0.02). CONCLUSIONS: Sensory manifestations in GB syndrome are often under-recognized and under-emphasized. This study analyzed the evolution and the profile of pain and paresthesia in GB syndrome during hospitalization. Knowledge, especially about evolution of pain and paresthesia during hospitalization might improve understanding and patient care.