100 research outputs found

    The puzzling story of flare inactive ultra fast rotating M dwarfs. I. Exploring their magnetic fields

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    Stars which are rapidly rotating are expected to show high levels of activity according to the activity-rotation relation. However, previous TESS studies have found Ultra Fast Rotating (UFR) M dwarfs with periods less than one day displaying low levels of flaring activity. As a result, in this study, we utilize VLT/FORS2 spectropolarimetric data of ten M dwarf UFR stars between spectral types ∼M2 - M6 all with Prot < 1, to detect the presence of a magnetic field. We divide our sample into rotation period bins of equal size, with one star having many more flares in the TESS lightcurve than the other. We also provide an analysis of the long-term variability within our sample usingTESS lightcurves taken during Cycles 1 and 3 (up to three years apart). We identify 605 flares from our sample which have energies between 2.0× 1031 and 5.4× 1034 erg. Although we find no significance difference in the flare rate between the Cycles, two of our targets display changes in their lightcurve morphology, potentially caused by a difference in the spot distribution. Overall, we find five stars (50 per cent) in our sample have a detectable magnetic field with strengths ∼1–2 kG. Of these five, four were the more flare active stars within the period bins with one being the less flare active star. It would appear the magnetic field strength may not be the answer to the lack of flaring activity and supersaturation or magnetic field configuration may play a role. However, it is clear the relationship between rotation and activity is more complex than a steady decrease over time

    The puzzling story of flare inactive ultra fast rotating M dwarfs. II. Searching for radial velocity variations

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    Observations made using TESS revealed a sample of low mass stars which show a periodic modulation on a period <0.2 d. Surprisingly many of these Ultra Fast Rotating (UFR) stars showed no evidence of flare activity which would be expected from such rapidly rotating stars. We present results from a spectroscopic survey of UFRs using the Nordic Optical Telescope to search for radial velocity variations which could reveal evidence for binarity. Our sample of 29 sources have a photometric period between 0.1-0.2d, cover spectral classes of M0-4V, and show no evidence for flares. We detect only one source with clear radial velocity shifts, with another two having Gaia RUWE values which suggests they are binaries. Further observations reveal the former star possibly contains a brown dwarf companion with a mass of M2>58 MJup and probability P(M2<90 MJup) = 50%. There is no evidence for the companion in our spectra, strengthening the case for a brown dwarf companion. We also examine the folded TESS light curves of all our targets, finding at least two are eclipsing binaries and one which has been contaminated by a spatially nearby δ Sct star. We estimate that around 1/4 of our targets may have been contaminated by short period variable stars. However, the majority of our targets are consistent with being single, low mass stars whose variability is due to starspots. We outline the possible reasons why they are not flare active despite being such rapid rotators

    Work Package 4 - Focus Group Overview. Grundtvig Multilateral - EU Lifelong Learning Programme. Project Number: 538955-LLP-1-2013-1-UK-GRUNDTVIG-GMP

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    During the first year of the RECOVEU project, the Consortium collected data regarding the policy and practice in the field of addiction treatment, education and social reintegration in all five countries.One of the major issues confronting policy makers and practitioners in the field of addiction and recovery is the lack of specific data concerning the access of adults in recovery to learning resources that enable them to recover and re‐integrate into society. Consulting with both adults in recovery and service providers will support awareness of the issues prevalent in recovering addicts’ lives and lead to the development of adult education which is responsive to the specific barriers this may raise. This will ensure that the adult education curriculum developed during the project will meet the needs of people in recovery, thereby increasing the potential for successful engagement and retention. Work Package 4 – Focus Group Phase has supported an understanding of the part played by adult education in an individual’s recovery process and provides a way in which people in recovery could be supported to engage in adult education opportunities. Each of the five partners delivered three to five focus groups, either with service users or service providers. The total number of participants was 92 (44 service users and 48 service providers), with a total number of 20 groups delivered across all partners. This review outlines the key findings from these focus groups

    Mapping the Radio Coronae of Cool Stars and Brown Dwarfs

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    The pulsing radio emission detected from ultracool dwarfs can be used as a powerful diagnostic of magnetic field strengths and topologies at and below the substellar boundary. Studies thus far have confirmed magnetic field strengths of 3 kG for two late M dwarfs and 1.7 kG for an L3.5 dwarf, the latter being the first confirmation of kG magnetic fields for an L dwarf. Ongoing long term monitoring of the radio pulses will also investigate the stability of the associated large‐scale magnetic fields over timescales > 1  year. We also present the preliminary results of a lengthy radio monitoring campaign of the rapidly rotating M4 star V374 Peg, with the resulting light curves phased with magnetic maps previously obtained through Zeeman Doppler Imaging. The radio emission from V374 Peg is strongly modulated by the large scale dipolar magnetic field, with two clear peaks in the radio light curve per period of rotation, occurring when the dipolar field lies in the plane of the sky. These results provide strong evidence that the electron cyclotron maser instability plays a pivotal role in the production of quiescent radio emission from V374 Peg, representing a significant departure from the accepted model of gyrosynchrotron emission as the dominant source of quiescent radio emission from active M dwarfs

    The Patient Feedback Response Framework – understanding why UK hospital staff find it difficult to make improvements based on patient feedback: A qualitative study

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    Patients are increasingly being asked for feedback about their healthcare experiences. However, healthcare staff often find it difficult to act on this feedback in order to make improvements to services. This paper draws upon notions of legitimacy and readiness to develop a conceptual framework (Patient Feedback Response Framework – PFRF) which outlines why staff may find it problematic to respond to patient feedback. A large qualitative study was conducted with 17 ward based teams between 2013 and 2014, across three hospital Trusts in the North of England. This was a process evaluation of a wider study where ward staff were encouraged to make action plans based on patient feedback. We focus on three methods here: i) examination of taped discussion between ward staff during action planning meetings ii) facilitators notes of these meetings iii) telephone interviews with staff focusing on whether action plans had been achieved six months later. Analysis employed an abductive approach. Through the development of the PFRF, we found that making changes based on patient feedback is a complex multi-tiered process and not something that ward staff can simply ‘do’. First, staff must exhibit normative legitimacy – the belief that listening to patients is a worthwhile exercise. Second, structural legitimacy has to be in place – ward teams need adequate autonomy, ownership and resource to enact change. Some ward teams are able to make improvements within their immediate control and environment. Third, for those staff who require interdepartmental co-operation or high level assistance to achieve change, organisational readiness must exist at the level of the hospital otherwise improvement will rarely be enacted. Case studies drawn from our empirical data demonstrate the above. It is only when appropriate levels of individual and organisational capacity to change exist, that patient feedback is likely to be acted upon to improve services
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