341 research outputs found
I looked at you, you looked at me, I smiled at you, you smiled at me—The impact of eye contact on emotional mimicry
Eye contact is an essential element of human interaction and direct eye gaze has been shown to have effects on a range of attentional and cognitive processes. Specifically, direct eye contact evokes a positive affective reaction. As such, it has been proposed that obstructed eye contact reduces emotional mimicry (i.e., the imitation of our counterpart’s emotions). So far, emotional mimicry research has used averted-gaze faces or unnaturally covered eyes (with black censor bars) to analyze the effect of eye contact on emotional mimicry. However, averted gaze can also signal disinterest/ disengagement and censor bars obscure eye-adjacent areas as well and hence impede emotion recognition. In the present study (N = 44), we used a more ecological valid approach by showing photos of actors who expressed either happiness, sadness, anger, or disgust while either wearing mirroring sunglasses that obstruct eye contact or clear glasses. The glasses covered only the direct eye region but not the brows, nose ridge, and cheeks. Our results confirm that participants were equally accurate in recognizing the emotions of their counterparts in both conditions (sunglasses vs. glasses). Further, in line with our hypotheses, participants felt closer to the targets and mimicked affiliative emotions more intensely when their counterparts wore glasses instead of sunglasses. For antagonistic emotions, we found the opposite pattern: Disgust mimicry, which was interpreted as an affective reaction rather than genuine mimicry, could be only found in the sunglasses condition. It may be that obstructed eye contact increased the negative impression of disgusted facial expressions and hence the negative feelings disgust faces evoked. The present study provides further evidence for the notion that eye contact is an important prerequisite for emotional mimicry and hence for smooth and satisfying social interactions.Peer Reviewe
Rapid variability at very high energies in Mrk 501
A major flaring state of the BL Lac object Mrk 501 was observed by the High
Energy Stereoscopic System (H.E.S.S.) in June, 2014. Flux levels higher than
one Crab unit were recorded and rapid variability at very high energies
(2-20 TeV) was revealed. The high statistics afforded by the flares
allowed us to probe the presence of minutes timescale variability and study its
statistical characteristics exclusively at TeV energies owing to the high
energy threshold of approximately 2 TeV. Doubling times of a few minutes are
estimated for fluxes greater than 2 TeV. Statistical tests on the light curves
show interesting temporal structure in the variations including deviations from
a normal flux distribution similar to those found in the PKS 2155-304 flare of
July 2006, at nearly an order of magnitude higher threshold energy. Rapid
variations at such high energies put strong constraints on the physical
mechanisms in the blazar jet.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherland
Higher heart rate variability predicts better affective interaction quality in non-intimate social interactions
Adaptive emotional responding is crucial for psychological well-being and the quality of social interactions. Resting heart rate variability (HRV), a measure of autonomic nervous system activity, has been suggested to index individual differences in emotion regulation (ER). As non-intimate social interactions require more regulatory efforts than intimate social interactions, we predicted that the association between HRV and affective interaction quality is moderated by the perceived intimacy of the exchange. Thus, we expected higher HRV to be particularly beneficial for affective interaction quality in non-intimate social interactions. Resting HRV was measured in the laboratory (N = 144). Subsequently, participants reported their affective interaction quality—as indicated by more positive and fewer negative emotions perceived in the self and the other—during an experience-sampling social interaction diary task. As predicted, in non-intimate interactions, individuals with higher HRV reported more positive and fewer negative emotions and perceived fewer negative emotions in their interaction partners. The results provide further insights into the relationship between HRV and emotional experiences during social interactions
Long term variability of the blazar PKS 2155-304
International audienceTime variability of the photon flux is a known feature of active galactic nuclei (AGN) and in particular of blazars. The high frequency peaked BL Lac (HBL) object PKS 2155-304 is one of the brightest sources in the TeV band and has been monitored regularly with different instruments and in particular with the H.E.S.S. experiment above 200 GeV for more than 11 years. These data together with the observations of other instruments and monitoring programs like SMARTS (optical), Swift-XRT/RXTE/XMM-Newton (X-ray) and Fermi-LAT (100 MeV < E < 300 GeV) are used to characterize the variability of this object in the quiescent state over a wide energy range. Variability studies are made by looking at the lognormality of the light curves and at the fractional root mean square (rms) variability F var in several energy bands. Lognormality is found in every energy range and the evolution of F var with the energy shows a similar increase both in X-rays and in TeV bands
Long-term optical variability of PKS 2155-304
Aims: The optical variability of the blazar PKS 2155-304 is investigated to
characterise the red noise behaviour at largely different time scales from 20
days to O(>10 yrs). Methods: The long-term optical light curve of PKS 2155-304
is assembled from archival data as well as from so-far unpublished observations
mostly carried out with the ROTSE-III and the ASAS robotic telescopes. A
forward folding technique is used to determine the best-fit parameters for a
model of a power law with a break in the power spectral density function (PSD).
The best-fit parameters are estimated using a maximum-likelihood method with
simulated light curves in conjunction with the Lomb Scargle Periodogram (LSP)
and the first-order Structure Function (SF). In addition, a new approach based
upon the so-called Multiple Fragments Variance Function (MFVF) is introduced
and compared to the other methods. Simulated light curves have been used to
confirm the reliability of these methods as well as to estimate the
uncertainties of the best-fit parameters. Results: The light curve is
consistent with the assumed broken power-law PSD. All three methods agree
within the estimated uncertainties with the MFVF providing the most accurate
results. The red-noise behaviour of the PSD in frequency f follows a power law
with f^-{\beta}, {\beta}=1.8 +0.1/-0.2 and a break towards f^0 at frequencies
lower than f_min=(2.7 +2.2/-1.6 yrs)^-1.Comment: 10 pages, 8 figures, the ROTSE-light curve can be downloaded from
http://vizier.cfa.harvard.edu/viz-bin/VizieR?-source=J/A+A/531/A12
A Mexican Hat with holes: calculating low resolution power spectra from data with gaps
A simple method for calculating a low-resolution power spectrum from data
with gaps is described. The method is a modification of the -variance
method previously described by Stutzki and Ossenkopf. A Mexican Hat filter is
used to single out fluctuations at a given spatial scale and the variance of
the convolved image is calculated. The gaps in the image, defined by the mask,
are corrected for by representing the Mexican Hat filter as a difference
between two Gaussian filters with slightly different widths, convolving the
image and mask with these filters and dividing the results before calculating
the final filtered image. This method cleanly compensates for data gaps even if
these have complicated shapes and cover a significant fraction of the data. The
method was developed to deal with problematic 2D images, where irregular
detector edges and masking of contaminating sources compromise the power
spectrum estimates, but it can also be straightforwardly applied to 1D timing
analysis or 3D data cubes from numerical simulations.Comment: accepted for publication in MNRA
Detailed spectral and morphological analysis of the shell type SNR RCW 86
Aims: We aim for an understanding of the morphological and spectral
properties of the supernova remnant RCW~86 and for insights into the production
mechanism leading to the RCW~86 very high-energy gamma-ray emission. Methods:
We analyzed High Energy Spectroscopic System data that had increased
sensitivity compared to the observations presented in the RCW~86 H.E.S.S.
discovery publication. Studies of the morphological correlation between the
0.5-1~keV X-ray band, the 2-5~keV X-ray band, radio, and gamma-ray emissions
have been performed as well as broadband modeling of the spectral energy
distribution with two different emission models. Results:We present the first
conclusive evidence that the TeV gamma-ray emission region is shell-like based
on our morphological studies. The comparison with 2-5~keV X-ray data reveals a
correlation with the 0.4-50~TeV gamma-ray emission.The spectrum of RCW~86 is
best described by a power law with an exponential cutoff at TeV and a spectral index of ~. A static
leptonic one-zone model adequately describes the measured spectral energy
distribution of RCW~86, with the resultant total kinetic energy of the
electrons above 1 GeV being equivalent to 0.1\% of the initial kinetic
energy of a Type I a supernova explosion. When using a hadronic model, a
magnetic field of ~100G is needed to represent the measured data.
Although this is comparable to formerly published estimates, a standard
E spectrum for the proton distribution cannot describe the gamma-ray
data. Instead, a spectral index of ~1.7 would be required, which
implies that ~erg has been transferred into
high-energy protons with the effective density cm^-3. This
is about 10\% of the kinetic energy of a typical Type Ia supernova under the
assumption of a density of 1~cm^-3.Comment: accepted for publication by A&
- …