178 research outputs found

    Bentuk Ketidakadilan terhadap Perempuan dalam Novel Jalan Bandungan Karya Nh. Dini

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    This research aims todescribe the form of marginalization of women seeninjustice, Subordination, stereotyping, violence, and workload,Which isexperienced by female characters in the novel Road Nh Bandungan work. he method usedisd escriptive method with qualitative form. The method used is descriptive method with qualitativ eform. in the form of 1) marginalization is exclusion due togender differences which resulted inpoverty. 2) subordination is the viewof gender, causesu bordinationof women. The notionthat women areirrational 3) stereoty pesare negative labeling of women 4) violence is (domestic violence and public violence), and 5) the work load is heavy and the allocation of a very long time

    Deriving photospheric parameters and elemental abundances for a sample of stars showing the FIP effect

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    One puzzling question in solar physics is the difference between elemental abundances in the photosphere and the corona. Elements with low first ionization potential (FIP) can be overabundant in the corona compared to the photosphere under certain circumstances. The same phenomenon has been observed on a handful of stars, while a few of them show the inverse effect. But not all the stars in the original sample had precise photospheric abundances derived from optical spectra, so for some the solar values were adopted. In this work we make homogeneous abundance measurements from optical spectroscopy. We collected spectra of 16 stars showing the FIP effect with the 1-m RCC telescope of Konkoly Observatory, with resolution of λ / Δ λ ˜ 21 000. We determine the fundamental astrophysical parameters (Teff, log g, [M/H], Οmic, v sin i) and individual elemental abundances with the SME spectral synthesis code using MARCS2012 model atmosphere and spectral line parameters from the Vienna Atomic Line Database (VALD)

    EI Eridani: a star under the influence -- The effect of magnetic activity in the short and long term

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    We use our photometric time series of more than forty years to analyze the long-term behaviour of EI Eri. Flare activity is investigated using space-borne photometric data obtained with TESS. The MUSICOS campaign aimed to achieve high-resolution spectroscopic observations from many sites around the globe, so that uninterrupted phase coverage of EI Eri became available. We use these data to reconstruct successive surface temperature maps of the star in order to study the changes of starspots on a very short timescale. We use long-term, seasonal period analysis of our photometric time series to study changes in the rotational period. Short-term Fourier-transform is also applied to look for activity cycle-like changes. We also study the phase and frequency distribution of hand-selected flares. We apply our multi-line Doppler imaging code to reconstruct four consecutive Doppler images. These images are also used to measure surface differential rotation by our cross-correlation technique. In addition, we carry out tests to demonstrate how Doppler imaging is affected by the fact that the data came from several different instruments with different spectral resolutions. Seasonal period analysis of the light curve reveals a smooth, significant change in period, possibly indicating the evolution of active latitudes. Temperature curves from B−VB-V and V−IV-I show slight differences, indicating the activity of EI Eri is spot dominated. Short-term Fourier transform reveals smoothly changing cycles between 4.5--5.5 and 8.9--11.6 years. The time-resolved spotted surface of EI Eri from Doppler imaging enabled us to follow the evolution of the different surface features. Cross-correlating the consecutive Doppler maps reveal surface shear of α=0.036±0.007\alpha=0.036\pm0.007. Our tests validate our approach and show that the surface temperature distribution is adequately reconstructed by our method.Comment: 14 pages, 13 figures, A&A accepte

    Superflares on the late-type giant KIC 2852961 -- Scaling effect behind flaring at different energy levels

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    The most powerful superflares reaching 1039^{39}erg bolometric energy are from giant stars. The mechanism behind flaring is supposed to be the magnetic reconnection, which is closely related to magnetic activity including starspots. However, it is poorly understood, how the underlying magnetic dynamo works and how the flare activity is related to the stellar properties which eventually control the dynamo action. We analyse the flaring activity of KIC 2852961, a late-type giant star, in order to understand how the flare statistics are related to that of other stars with flares and superflares and what the role of the observed stellar properties in generating flares is. We search for flares in the full Kepler dataset of the star by an automated technique together with visual inspection. We set a final list of 59 verified flares during the observing term. We calculate flare energies for the sample and perform a statistical analysis. The stellar properties of KIC 2852961 are revised and a more consistent set of parameters are proposed. The cumulative flare energy distribution can be characterized by a broken power-law, i.e. on the log-log representation the distribution function is fitted by two linear functions with different slopes, depending on the energy range fitted. We find that the total flare energy integrated over a few rotation periods correlates with the average amplitude of the rotational modulation due to starspots. Flares and superflares seem to be the result of the same physical mechanism at different energetic levels, also implying that late-type stars in the main sequence and flaring giant stars have the same underlying physical process for emitting flares. There might be a scaling effect behind generating flares and superflares in the sense that the higher the magnetic activity the higher the overall magnetic energy released by flares and/or superflares.Comment: 14 pages, 17 figures, 4 tables, accepted for publication in Astronomy and Astrophysic

    Go-stimuli proportion influences response strategy in a sustained attention to response task

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    The sustained attention to response task (SART) usefulness as a measure of sustained attention has been questioned. The SART may instead be a better measure of other psychological processes and could prove useful in understanding some real-world behaviours. Thirty participants completed four Go/No-Go response tasks much like the SART, with Go-stimuli proportions of .50, .65, .80 and .95. As Go-stimuli proportion increased, reaction times decreased while both commission errors and self-reported task-related thoughts increased. Performance measures were associated with task-related thoughts but not taskunrelated thoughts. Instead of faster reaction times and increased commission errors being due to absentmindedness or perceptual decoupling from the task, the results suggested participants made use of two competing response strategies, in line with a response strategy or response inhibition perspective of SART performance. Interestingly, performance measures changed in a nonlinear manner, despite the linear Go proportion increase. A threshold may exist where the prepotent motor response becomes more pronounced, leading to the disproportionate increase in response speed and commission errors. This research has implications for researchers looking to employ the SAR

    The Weakening Outburst of the Young Eruptive Star V582 Aur

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    V582 Aur is a pre-main sequence FU Orionis type eruptive star, which entered a brightness minimum in 2016 March due to changes in the line-of-sight extinction. Here, we present and analyze new optical BB, VV, RCR_C and ICI_C band multiepoch observations and new near-infrared JJ, HH and KSK_S band photometric measurements from 2018 January−-2019 February, as well as publicly available mid-infrared WISE data. We found that the source shows a significant optical−-near-infrared variability, and the current brightness minimum has not completely finished yet. If the present dimming originates from the same orbiting dust clump that caused a similar brightness variation in 2012, than our results suggest a viscous spreading of the dust particles along the orbit. Another scenario is that the current minimum is caused by a dust structure, that is entering and leaving the inner part of the system. The WISE measurements could be consistent with this scenario. Our long-term data, as well as an accretion disk modeling hint at a general fading of V582 Aur, suggesting that the source will reach the quiescent level in ∌\sim80 years.Comment: 8 pages, 4 figures, accepted for publication in Ap

    The quest for stellar coronal mass ejections in late-type stars: I. Investigating Balmer-line asymmetries of single stars in Virtual Observatory data

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    Context. Flares and coronal mass ejections (CMEs) can have deleterious effects on their surroundings: they can Erode or completely destroy atmospheres of orbiting planets over time and also have high importance in stellar evolution. Most of the CME detections in the literature are single events found serendipitously sparse for statistical investigation. Aims. We aimed to gather a large amount of spectral data of M-dwarfs to drastically increase the number of known events to make statistical analysis possible in order to study the properties of potential stellar CMEs. Methods. Using archival spectral data we investigated asymmetric features of Balmer-lines, which could indicate the Doppler-signature of ejected material. Results. Of more than 5500 spectra we find 478 that have line asymmetries - including nine larger events, in terms of velocity and mass - on 25 objects, with 1.2-19.6 events per day on objects with line asymmetries. Most events are connected with enhanced peaks of Balmer-lines, indicating that these are connected to flares similar to solar events. In most cases the detected speed does not reach surface escape velocity: the typical observed maximum velocities are on the order of 100-300 km s -1 , while the typical masses of the ejecta were on the order of 10 15 -10 18 g. Statistical analysis of the events suggests that these events are more frequent on cooler stars with stronger chromospheric activity. Conclusions. If the detected events correspond to CMEs, the detected maximum velocities are lower than those observed on the Sun, while event rates were somewhat lower than we could expect from the solar case. If the velocities are not distorted significantly due to a projection effect, these findings may support the idea that most of the coronal mass ejections could be suppressed by a strong magnetic field. Alternatively, it is possible that we can observe only an early low-coronal phase of the events before being accelerated at higher altitudes. Our findings could indicate that later-type, active dwarfs could be a safer environment for exoplanetary systems CME-wise than previously thought, and atmosphere loss due to radiation effects would play a stronger role in exoplanetary atmosphere evolution than CMEs

    Spontaneous and deliberate future thinking: A dual process account

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    © 2019 Springer Nature.This is the final published version of an article published in Psychological Research, licensed under a Creative Commons Attri-bution 4.0 International License. Available online at: https://doi.org/10.1007/s00426-019-01262-7.In this article, we address an apparent paradox in the literature on mental time travel and mind-wandering: How is it possible that future thinking is both constructive, yet often experienced as occurring spontaneously? We identify and describe two ‘routes’ whereby episodic future thoughts are brought to consciousness, with each of the ‘routes’ being associated with separable cognitive processes and functions. Voluntary future thinking relies on controlled, deliberate and slow cognitive processing. The other, termed involuntary or spontaneous future thinking, relies on automatic processes that allows ‘fully-fledged’ episodic future thoughts to freely come to mind, often triggered by internal or external cues. To unravel the paradox, we propose that the majority of spontaneous future thoughts are ‘pre-made’ (i.e., each spontaneous future thought is a re-iteration of a previously constructed future event), and therefore based on simple, well-understood, memory processes. We also propose that the pre-made hypothesis explains why spontaneous future thoughts occur rapidly, are similar to involuntary memories, and predominantly about upcoming tasks and goals. We also raise the possibility that spontaneous future thinking is the default mode of imagining the future. This dual process approach complements and extends standard theoretical approaches that emphasise constructive simulation, and outlines novel opportunities for researchers examining voluntary and spontaneous forms of future thinking.Peer reviewe
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