Relevant bibliographies by topics / Stars: individual (Fomalhaut A)

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  2. Dissertations / Theses
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Academic literature on the topic 'Stars: individual (Fomalhaut A)'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Stars: individual (Fomalhaut A)"

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Ruban, E. V., and A. A. Arkharov. "Young stars in gas-dust disks. I. Fomalhaut." Astrophysics 55, no. 1 (2012): 53–69. http://dx.doi.org/10.1007/s10511-012-9222-0.

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Stamm, Johann, Andrzej Czechowski, Ingrid Mann, Carsten Baumann, and Margaretha Myrvang. "Dust trajectory simulations around the Sun, Vega, and Fomalhaut." Astronomy & Astrophysics 626 (June 2019): A107. http://dx.doi.org/10.1051/0004-6361/201834727.

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Context. Vega and Fomalhaut display a thermal emission brightness that could possibly arise from hot dust near the stars, an inner extension of their planetary debris disks. An idea has been suggested that nanometer-sized dust particles are kept in the vicinity of the stars by electromagnetic forces. This resembles the trapping that model calculations show in the corotating magnetic field in the inner heliosphere within approximately 0.2 AU from the Sun. Aims. The aim of this work is to study whether the trapping of dust due to electromagnetic forces acting on charged dust near the Sun can occur around Vega and Fomalhaut and what are the conditions for trapping. Methods. We studied the dust trajectories with numerical calculations of the full equation of motion, as well as by using the guiding center approximation. We assumed a constant dust charge and a Parker-type magnetic field, which we estimated for the two stars. Results. We find no bound trajectories of charged particles around Vega or Fomalhaut as long as the radiation pressure force exceeds the gravitational force, that is, for particles smaller than 1 μm. A trapping zone could exist inside of 0.02 AU for Vega and 0.025 AU for Fomalhaut, but only for those particles with radiation pressure force smaller than gravitational force. In comparison to the Sun, the trapping conditions would occur closer to the stars because their faster rotation leads to a more closely wound-up magnetic field spiral. We also show that plasma corotation can be consistent with trapping. Our model calculations show that the charged particles are accelerated to stellar wind velocity very quickly, pass 1 AU after approximately three days, and are further ejected outward where they pass the debris disks at high velocity. We find this for particles with a surface charge-to-mass ratio larger than 10−6 elementary charges per proton mass for both negatively and positively charged dust and independent of the strength of the radiation pressure force. Based on charging assumptions, this would correspond to dust of sizes 100 nm and smaller.
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Nielsen, Eric L., Michael C. Liu, Zahed Wahhaj, Beth A. Biller, and Thomas L. Hayward. "The Gemini NICI Planet-Finding Campaign: The Frequency of Giant Planets around Young B and A Stars." Proceedings of the International Astronomical Union 8, S299 (2013): 60–61. http://dx.doi.org/10.1017/s1743921313007874.

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AbstractWe have carried out high contrast imaging of 70 young, nearby B and A stars to search for brown dwarf and planetary companions as part of the Gemini NICI Planet-Finding Campaign. Our survey represents the largest, deepest survey for planets around high-mass stars (≈1.5–2.5 M⊙) conducted to date and includes the planet hosts β Pic and Fomalhaut. Despite detecting two new brown dwarfs, our observations did not detect new planets around our target stars, and we present upper limits on the fraction of high-mass stars that can host giant planets that are consistent with our null result.
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Di Folco, Emmanuel, Pierre Kervella, Frédéric Thévenin, Pierre Morel, Armando Domiciano de Suza та Vincent Coudé du Foresto. "Near-IR Observations of Vega-like Stars with the VLTI: β Pic, α PsA, ∊ Eri and τ Cet". Symposium - International Astronomical Union 219 (2004): 75–79. http://dx.doi.org/10.1017/s0074180900181975.

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We have conducted K band interferometric observations of four nearby main-sequence Vega-like stars at the VLTI with very long baselines. The very high resolution allowed us to probe the innermost region of the disks, where planets are supposed to be formed. The diameters of three bright and nearby prototypes β Pictoris, Fomalhaut (α PsA) and ∊ Eridani as well as τ Ceti have been measured with VINCI, the VLTI commissioning instrument, with a high accuracy. The derived diameters were used to constrain their age with help of the evolution code CESAM. The precision achieved with VINCI allowed us to discuss the shape of their photosphere and the possible detection of warm circumstellar material within the narrow interferometric field of view.
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Shannon, Andrew, Cathie Clarke, and Mark Wyatt. "Dancing with the stars: formation of the Fomalhaut triple system and its effect on the debris discs." Monthly Notices of the Royal Astronomical Society 442, no. 1 (2014): 142–47. http://dx.doi.org/10.1093/mnras/stu846.

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Su, Kate Y. L., and G. H. Rieke. "Signposts of Multiple Planets in Debris Disks." Proceedings of the International Astronomical Union 8, S299 (2013): 318–21. http://dx.doi.org/10.1017/s1743921313008764.

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AbstractWe review the nearby debris disk structures revealed by multi-wavelength images from Spitzer and Herschel, and complemented with detailed spectral energy distribution modeling. Similar to the definition of habitable zones around stars, debris disk structures should be identified and characterized in terms of dust temperatures rather than physical distances so that the heating power of different spectral type of stars is taken into account and common features in disks can be discussed and compared directly. Common features, such as warm (~150 K) dust belts near the water-ice line and cold (~50 K) Kuiper-belt analogs, give rise to our emerging understanding of the levels of order in debris disk structures and illuminate various processes about the formation and evolution of exoplanetary systems. In light of the disk structures in the debris disk twins (Vega and Fomalhaut), and the current limits on the masses of planetary objects, we suggest that the large gap between the warm and cold dust belts is the best signpost for multiple (low-mass) planets beyond the water-ice line.
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Padgett, Deborah L. "SpS1-Preparing for the harvest from large infrared surveys." Proceedings of the International Astronomical Union 5, H15 (2009): 510–11. http://dx.doi.org/10.1017/s1743921310010422.

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During the past decade, there has been a revolution in the availability of multi-wavelength astronomical surveys. From the Sloan Digital Sky Survey (SDSS) to the NRAO VLA Sky Survey (NVSS), astronomical research based on publicly accessible datasets is becoming standard practice in the community. Beginning with the Infrared Astronomical Satellite (IRAS) mission, infrared surveys have played a critical role in stellar astronomy by identifying cool and dusty stars worthy of spectroscopic characterization. IRAS' four photometric bands at 12, 25, 60, and 100 μm were ideal for detecting dusty circumstellar material. All-sky surveys like IRAS reveal the brightest members of each class of rare objects, optimizing their follow-up strategy. The case of debris disks around main sequence stars demonstrates this utility. IRAS detected dust disks around four nearby stars, Beta Pictoris, Fomalhaut, Epsilon Eridani, and Vega. The “Fabulous Four” remain the best studied debris disks, despite hundreds of additional examples discovered by the Spitzer Space Telescope. In the nearly 30 years since IRAS was launched, its highly reliable catalog of just 250000 sources, modest by modern standards, with arcminute scale resolution and 0.3 - 1 Jy sensitivity, has generated over 10,000 references in ADS. This is a success story by any measure.
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Rebollido, I., C. Eiroa, B. Montesinos, et al. "The co-existence of hot and cold gas in debris discs." Astronomy & Astrophysics 614 (June 2018): A3. http://dx.doi.org/10.1051/0004-6361/201732329.

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Context. Debris discs have often been described as gas-poor discs as the gas-to-dust ratio is expected to be considerably lower than in primordial, protoplanetary discs. However, recent observations have confirmed the presence of a non-negligible amount of cold gas in the circumstellar (CS) debris discs around young main-sequence stars. This cold gas has been suggested to be related to the outgassing of planetesimals and cometary-like objects. Aims. The goal of this paper is to investigate the presence of hot gas in the immediate surroundings of the cold-gas-bearing debris-disc central stars. Methods. High-resolution optical spectra of all currently known cold-gas-bearing debris-disc systems, with the exception of β Pic and Fomalhaut, have been obtained from La Palma (Spain), La Silla (Chile), and La Luz (Mexico) observatories. To verify the presence of hot gas around the sample of stars, we have analysed the Ca II H&K and the Na I D lines searching for non-photospheric absorptions of CS origin, usually attributed to cometary-like activity. Results. Narrow, stable Ca II and/or Na I absorption features have been detected superimposed to the photospheric lines in 10 out of the 15 observed cold-gas-bearing debris-disc stars. Features are found at the radial velocity of the stars, or slightly blue- or red-shifted, and/or at the velocity of the local interstellar medium (ISM). Some stars also present transient variable events or absorptions extended towards red wavelengths (red wings). These are the first detections of such Ca II features in 7 out of the 15 observed stars. Although an ISM origin cannot categorically be excluded, the results suggest that the stable and variable absorptions arise from relatively hot gas located in the CS close-in environment of the stars. This hot gas is detected in at least ~80%, of edge-on cold-gas-bearing debris discs, while in only ~10% of the discs seen close to face-on. We interpret this result as a geometrical effect, and suggest that the non-detection of hot gas absorptions in some face-on systems is due to the disc inclination and likely not to the absence of the hot-gas component. This gas is likely released in physical processes related in some way to the evaporation of exocomets, evaporation of dust grains, or grain-grain collisions close to the central star.
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Heap, Sara R., Dennis Ebbets, Eliot M. Malumuth, Stephen P. Maran, Alex de Koter, and Ivan Hubeny. "GHRS Spectroscopy of individual stars in R136a." Astrophysical Journal 435 (November 1994): L39. http://dx.doi.org/10.1086/187589.

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Kennedy, Grant M. "The unexpected narrowness of eccentric debris rings: a sign of eccentricity during the protoplanetary disc phase." Royal Society Open Science 7, no. 6 (2020): 200063. http://dx.doi.org/10.1098/rsos.200063.

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This paper shows that the eccentric debris rings seen around the stars Fomalhaut and HD 202628 are narrower than expected in the standard eccentric planet perturbation scenario (sometimes referred to as ‘pericentre glow’). The standard scenario posits an initially circular and narrow belt of planetesimals at semi-major axis a , whose eccentricity is increased to e f after the gas disc has dispersed by secular perturbations from an eccentric planet, resulting in a belt of width 2 ae f . In a minor modification of this scenario, narrower belts can arise if the planetesimals are initially eccentric, which could result from earlier planet perturbations during the gas-rich protoplanetary disc phase. However, a primordial eccentricity could alternatively be caused by instabilities that increase the disc eccentricity, without the need for any planets. Whether these scenarios produce detectable eccentric rings within protoplanetary discs is unclear, but they nevertheless predict that narrow eccentric planetesimal rings should exist before the gas in protoplanetary discs is dispersed. PDS 70 is noted as a system hosting an asymmetric protoplanetary disc that may be a progenitor of eccentric debris ring systems.
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Dissertations / Theses on the topic "Stars: individual (Fomalhaut A)"

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MacGregor, Meredith A., Luca Matra, Paul Kalas, et al. "A Complete ALMA Map of the Fomalhaut Debris Disk." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/624433.

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We present ALMA mosaic observations at 1.3. mm (223 GHz) of the Fomalhaut system with a sensitivity of 14 mu Jy/beam. These observations provide the first millimeter map of the continuum dust emission from the complete outer debris disk with uniform sensitivity, enabling the first conclusive detection of apocenter glow. We adopt an MCMC modeling approach that accounts for the eccentric orbital parameters of a collection of particles within the disk. The outer belt is radially confined with an inner edge of 136.3 +/- 0.9. au and width of 13.5 +/- 1.8. au. We determine a best-fit eccentricity of 0.12 +/- 0.01. Assuming a size distribution power-law index of q. =. 3.46 +/- 0.09, we constrain the dust absorptivity power-law index a to be 0.9 <beta <. 1.5. The geometry of the disk is robustly constrained with inclination 65 degrees. 6 +/- 0 degrees. 3, position angle 337 degrees 9 +/- 0 degrees.3, and argument of periastron 22 degrees.5 +/- 4 degrees. 3. Our observations do not confirm any of the azimuthal features found in previous imaging studies of the disk with Hubble Space Telescope, SCUBA, and ALMA. However, we cannot rule out structures. 10 au in size or that only affect smaller grains. The central star is clearly detected with a flux density of 0.75 +/- 0.02. mJy, significantly lower than predicted by current photospheric models. We discuss the implications of these observations for the directly imaged Fomalhaut b and the inner dust belt detected at infrared wavelengths.
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Matra, L., M. A. MacGregor, P. Kalas, et al. "Detection of Exocometary CO within the 440Myr Old Fomalhaut Belt: A Similar CO+ CO2 Ice Abundance in Exocomets and Solar System Comets." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/624435.

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Recent Atacama Large Millimeter/submillimeter Array observations present mounting evidence for the presence of exocometary gas released within Kuiper Belt analogs around nearby main-sequence stars. This represents a unique opportunity to study their ice reservoir at the younger ages when volatile delivery to planets is most likely to occur. We here present the detection of CO J=2-1 emission colocated with dust emission from the cometary belt in the 440 Myr old Fomalhaut system. Through spectrospatial filtering, we achieve a 5.4s detection and determine that the ring's sky-projected rotation axis matches that of the star. The CO mass derived (0.65-42) x10(-7) M-circle plus is the lowest of any circumstellar disk detected to date and must be of exocometary origin. Using a steady-state model, we estimate the CO+ CO2 mass fraction of exocomets around Fomalhaut to be between 4.6% and 76%, consistent with solar system comets and the two other belts known to host exocometary gas. This is the first indication of a similarity in cometary compositions across planetary systems that may be linked to their formation scenario and is consistent with direct interstellar medium inheritance. In addition, we find tentative evidence that(49 +/- 27)% of the detected flux originates from a region near the eccentric belt's pericenter. If confirmed, the latter may be explained through a recent impact event or CO pericenter glow due to exocometary release within a steady-state collisional cascade. In the latter scenario, we show how the azimuthal dependence of the CO release rate leads to asymmetries in gas observations of eccentric exocometary belts.
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Spruyt, Jon. "Gamified Individual Brainstorming : Reaching for the stars." Thesis, Umeå universitet, Institutionen för informatik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-133603.

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Ideation is a critical step in the creation of new solutions to problems. Brainstorming, being the most commonly known ideation method, is mostly done in groups. However, research points out that brainstorming individually is more effective than brainstorming in groups. This paper investigates if negative aspects (reduced enjoyment, motivation and self-rated performance) associated with brainstorming alone can be overcome by using a gamified approach to brainstorming. Gamified and non-gamified prototypes have been made and used in combination with a questionnaire to measure differences in these negative aspects. From the within-subject study including 20 participants, it appears that the implemented gamification approach was not different from the non-gamified approach for most of the negative aspects. Self-rated performance was however significantly higher in the non-gamified version. Using the gamified or non-gamified approach seems to largely come down to the preference of the user.
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Fossati, L., T. Koskinen, K. France, et al. "Suppressed Far-UV Stellar Activity and Low Planetary Mass Loss in the WASP-18 System." IOP PUBLISHING LTD, 2018. http://hdl.handle.net/10150/627089.

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WASP-18 hosts a massive, very close-in Jupiter-like planet. Despite its young age (< 1 Gyr), the star presents an anomalously low stellar activity level: the measured log R'(HK) activity parameter lies slightly below the basal level; there is no significant time-variability in the log R'(HK) value; there is no detection of the star in the X-rays. We present results of far-UV observations of WASP-18 obtained with COS on board of Hubble Space Telescope aimed at explaining this anomaly. From the star's spectral energy distribution, we infer the extinction (E(B-V) approximate to 0.01 mag) and then the interstellar medium (ISM) column density for a number of ions, concluding that ISM absorption is not the origin of the anomaly. We measure the flux of the four stellar emission features detected in the COS spectrum (C II, C III, C IV, Si IV). Comparing the C II/C IV flux ratio measured for WASP-18 with that derived from spectra of nearby stars with known age, we see that the far-UV spectrum of WASP-18 resembles that of old (> 5 Gyr), inactive stars, in stark contrast with its young age. We conclude that WASP-18 has an intrinsically low activity level, possibly caused by star-planet tidal interaction, as suggested by previous studies. Re-scaling the solar irradiance reference spectrum to match the flux of the Si IV line, yields an XUV integrated flux at the planet orbit of 10.2 erg s(-1) cm(-2). We employ the rescaled XUV solar fluxes to models of the planetary upper atmosphere, deriving an extremely low thermal mass-loss rate of 10(-20) M-J Gyr(-1). For such high-mass planets, thermal escape is not energy limited, but driven by Jeans escape.
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Brunsden, Emily. "The Music of the Stars : Spectroscopy of Pulsations in gamma Doradus Stars." Thesis, University of Canterbury. Astronomy, 2013. http://hdl.handle.net/10092/8373.

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The mysteries of the interior structures of stars are being tackled with asteroseismology. The observable parameters of the surface pulsations of stars inform us of the interior characteristics of numerous classes of stars. The main-sequence gamma Doradus stars, just a little hotter than the Sun, offer the potential of determining stellar structure right down to the core. To determine the structural profile of a star, the observed frequencies and a full geometric description must be determined. This is only possible with long-term spectroscopic monitoring and careful analysis of the pulsation signature in spectral lines. This work seeks to identify the pulsational geometry of several gamma Doradus stars and to identify areas of improvement for current observation, analysis and modelling techniques. More than 4500 spectra were gathered on five stars for this purpose. For three stars a successful multi-frequency and mode identification solution was determined and significant progress has been made towards the understanding of a binary system involving a gammaDoradus star. A hybrid gamma Doradus/\delta Scuti pulsator was also intensely monitored and results from this work raise important questions about the classification of this type of star. Current analysis techniques were found to be fit-for-purpose for pure gamma Doradus stars, but stars with complexities such as hybrid pulsations and/or fast rotation require future development of the current models.
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Boyajian, Tabetha S., Roi Alonso, Alex Ammerman, et al. "The First Post-Kepler Brightness Dips of KIC 8462852." IOP PUBLISHING LTD, 2018. http://hdl.handle.net/10150/626540.

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We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in 2015 October, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1%-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and " Angkor," which persist on timescales from several days to weeks. Our main results so far are as follows: (i) there are no apparent changes of the stellar spectrum or polarization during the dips and (ii) the multiband photometry of the dips shows differential reddening favoring non-gray extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale << 1 mu m, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process.
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Tutar, Özdarcan D., P. S. Smith, and V. Keskin. "Time-resolved spectropolarimetric observations of polars WX LMi and BY Cam." OXFORD UNIV PRESS, 2017. http://hdl.handle.net/10150/624423.

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Time-series spectropolarimetric observations of polar WX LMi and asynchronous polar BY Cam are presented. Magnetic field properties, radial velocities and optical polarization are investigated via consecutive observations with good phase sampling during a single orbital cycle. Both systems are found to have a decentred dipole magnetic field configuration. One of the poles of WX LMi has a field strength of 49 MG, while the other pole may have possible field strengths of 69, 104 or 207 MG, depending on the harmonic numbers of the cyclotron humps observed in the circularly polarized spectrum. For BY Cam, a field strength of 168 MG is found for one of the poles, while field strengths of 70, 160 or 212 MG are possible for the other pole.
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Lew, Ben W. P., Daniel Apai, Yifan Zhou, et al. "CLOUD ATLAS: DISCOVERY OF PATCHY CLOUDS AND HIGH-AMPLITUDE ROTATIONAL MODULATIONS IN A YOUNG, EXTREMELY RED L-TYPE BROWN DWARF." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/622769.

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Condensate clouds fundamentally impact the atmospheric structure and spectra of exoplanets and brown dwarfs, but the connections between surface gravity, cloud structure, dust in the upper atmosphere, and the red colors of some brown dwarfs remain poorly understood. Rotational modulations enable the study of different clouds in the same atmosphere, thereby providing a method to isolate the effects of clouds. Here, we present the discovery of high peak-to-peak amplitude (8%) rotational modulations in a low-gravity, extremely red (J-K-s = 2.55) L6 dwarf WISEP J004701.06+680352.1 (W0047). Using the Hubble Space Telescope (HST) time-resolved grism spectroscopy, we find a best-fit rotational period (13.20 +/- 0.14 hr) with a larger amplitude at 1.1 mu m than at 1.7 mu m. This is the third-largest near-infrared variability amplitude measured in a brown dwarf, demonstrating that large-amplitude variations are not limited to the L/T transition but are present in some extremely red L-type dwarfs. We report a tentative trend between the wavelength dependence of relative amplitude, possibly proxy for small dust grains lofted in the upper atmosphere, and the likelihood of large-amplitude variability. By assuming forsterite as a haze particle, we successfully explain the wavelength-dependent amplitude with submicron-sized haze particle sizes of around 0.4 mu m. W0047 links the earlier spectral and later spectral type brown dwarfs in which rotational modulations have been observed; the large amplitude variations in this object make this a benchmark brown dwarf for the study of cloud properties close to the L/T transition.
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Kiminki, Megan M., Megan Reiter та Nathan Smith. "Ancient eruptions of η Carinae: a tale written in proper motions". OXFORD UNIV PRESS, 2016. http://hdl.handle.net/10150/622109.

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We analyse eight epochs of Hubble Space Telescope H alpha+[N ii] imaging of eta Carinae's outer ejecta. Proper motions of nearly 800 knots reveal that the detected ejecta are divided into three apparent age groups, dating to around 1250 A.D., to around 1550 A.D., and to during or shortly before the Great Eruption of the 1840s. Ejecta from these groups reside in different locations and provide a firm constraint that eta Car experienced multiple major eruptions prior to the nineteenth century. The 1250 and 1550 events did not share the same axisymmetry as the Homunculus; the 1250 event was particularly asymmetric, even one-sided. In addition, the ejecta in the S ridge, which have been associated with the Great Eruption, appear to predate the ejection of the Homunculus by several decades. We detect essentially ballistic expansion across multiple epochs. We find no evidence for large-scale deceleration of the observed knots that could power the soft X-ray shell by ploughing into surrounding material, suggesting that the observed X-rays arise instead from fast, rarefied ejecta from the 1840s overtaking the older dense knots. Early deceleration and subsequent coasting cannot explain the origin of the older outer ejecta - significant episodic mass loss prior to the nineteenth century is required. The time-scale and geometry of the past eruptions provide important constraints for any theoretical physical mechanisms driving eta Car's behaviour. Non-repeating mechanisms such as the merger of a close binary in a triple system would require additional complexities to explain the observations.
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Currie, Thayne, Olivier Guyon, Motohide Tamura, et al. "Subaru/SCExAO First-light Direct Imaging of a Young Debris Disk around HD 36546." IOP PUBLISHING LTD, 2017. http://hdl.handle.net/10150/624379.

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We present H-band scattered light imaging of a bright debris disk around the A0 star HD 36546 obtained from the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system with data recorded by the HiCIAO camera using the vector vortex coronagraph. SCExAO traces the disk from r similar to 0."3 to r similar to 1" (34-114 au). The disk is oriented in a near east-west direction (PA similar to 75 degrees), is inclined by i similar to 70 degrees-75 degrees, and is strongly forward-scattering (g > 0.5). It is an extended disk rather than a sharp ring; a second, diffuse dust population extends from the disk's eastern side. While HD 36546 intrinsic properties are consistent with a wide age range (t similar to 1-250 Myr), its kinematics and analysis of coeval stars suggest a young age (3-10 Myr) and a possible connection to Taurus-Auriga's star formation history. SCExAO's planet-to-star contrast ratios are comparable to the first-light Gemini Planet Imager contrasts; for an age of 10 Myr, we rule out planets with masses comparable to HR 8799 b beyond a projected separation of 23 au. A massive icy planetesimal disk or an unseen super-Jovian planet at r > 20 au may explain the disk's visibility. The HD 36546 debris disk may be the youngest debris disk yet imaged, is the first newly identified object from the now-operational SCExAO extreme AO system, is ideally suited for spectroscopic follow-up with SCExAO/CHARIS in 2017, and may be a key probe of icy planet formation and planet-disk interactions.
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Books on the topic "Stars: individual (Fomalhaut A)"

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Gründler, Gabriela. Stars of suburbia. Edition Patrick Frey, 2001.

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Bilhana. Black marigolds: And, Coloured stars. Anvil Press Poetry, 2004.

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Yosano,Akiko 与謝野,晶子 (1878-1942). River of stars: Selected poems of Yosano Akiko. Shambhala Publications, 1996.

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Grundler, Gabriela, and Gabriela Grindler. Stars of Suburbia. Scalo Publishers, 2001.

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A, Matilsky Terry, and United States. National Aeronautics and Space Administration., eds. Ultraviolet properties of individual hot stars in globular cluster cores. National Aeronautics and Space Administration, 1992.

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Rigby and Elsie Nelley. Rigby PM Stars: Individual Student Edition Yellow Kris's Family. Rigby Education, 2012.

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Rigby and Debbie Croft. Rigby PM Stars: Individual Student Edition Red the Race. Rigby Education, 2012.

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Smith, Annette, and Rigby. Rigby PM Stars: Individual Student Edition Red Lily's Apple. Rigby Education, 2012.

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Rigby PM Stars: Individual Student Edition Green A Firefighter. RIGBY, 2012.

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Rigby PM Stars: Individual Student Edition Blue Painting Faces. Rigby Education, 2012.

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Book chapters on the topic "Stars: individual (Fomalhaut A)"

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Unsöld, Albrecht, and Bodo Baschek. "The Sun and Stars. Astrophysics of Individual Stars." In Heidelberg Science Library. Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-662-02681-6_4.

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Sills, Alison. "Models of Individual Blue Stragglers." In Ecology of Blue Straggler Stars. Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-662-44434-4_12.

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Barbuy, B. "Abundances in Individual Stars of the Galactic Bulge." In Galaxy Evolution: Connecting the Distant Universe with the Local Fossil Record. Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4213-7_67.

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Gavryusev, V. G., and E. A. Gavryuseva. "Line Profiles and Rotational Splitting of Individual P-Modes." In New Eyes to See Inside the Sun and Stars. Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4982-2_32.

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Luri, X., M. O. Mennessier, F. Figueras, and J. Torra. "Group identification and individual assignation of stars from kinematical and luminosity parameters." In New Approaches in Classification and Data Analysis. Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-51175-2_78.

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Sion, Edward M. "White Dwarf Mass Loss, Rotation, Individual Masses and the Identification of the White Dwarf Remnants of Upper Main Sequence Stars." In Angular Momentum and Mass Loss for Hot Stars. Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-2105-4_36.

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McNally, Derek. "Joint Commission Meeting 5, JCM5: Spectroscopy of Individual Stars in Globular Clusters and the Early Chemical Evolution of our Galaxy." In Highlights of Astronomy. Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0977-9_109.

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"Individual, Single Stars." In Hipparcos, the New Reduction of the Raw Data. Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6342-8_3.

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Stevens, Martin. "Stars of the Tactile World." In Secret Worlds. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198813675.003.0005.

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This chapter addresses the supreme level of refinement found in many animals for analysing tactile and pressure information. It begins by looking at the sensory organ of the star-nosed mole. The mole’s star-shaped organ is used purely for collecting tactile information. The chapter then considers the Eimer’s organs which cover every appendage that comprises the nose, some of which are used for initial prey detection, while others are for identification. Owing to the number of Eimer’s organs, their tiny size, and the way that the sensory cells respond to patterns of stimulation across parts of each individual Eimer’s organ, the mole obtains exquisite detail on texture, almost to a microscopic level. The chapter also discusses the highly refined tactile sense of spiders, looking at how they rely on vibrations transmitted through the ground, the silk web strands, or the surface waves and air for prey detection and capture. Spiders are equipped with a variety of sensors to detect mechanical information, including fine hairs sensitive to wind movement and touch, and special organs called slit sensilla around the joints of legs that measure physical forces acting on the exoskeleton. Finally, the chapter studies the nature and function of integumentary sense organs or ISOs in both crocodiles and alligators. The heavily built bodies of crocodiles and alligators belie a high sensitivity, being able to detect the slightest changes in touch and pressure.
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Basu, Sarbani, and William J. Chaplin. "Interpreting Frequencies of Individual Modes: Comparing Frequencies." In Asteroseismic Data Analysis. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691162928.003.0008.

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This chapter discusses different ways in which one can use the frequencies to determine stellar properties. It considers straightforward comparisons of observed frequencies with those of stellar models, as well as the limitations and challenges of such comparisons. Different approaches are used to model stars whose frequencies have been observed. Some methods are similar to what is done if only the nonseismic properties of a star are known. Other methods make use of the fact that the average asteroseismic data give a good indication of the mass and radius of the star being modeled, and so these methods construct models around that mass and radius. Yet other methods involve optimization schemes. However, even the most complex optimization schemes used thus far do not explore the effects of all inputs and parameters that can be varied while constructing stellar models.
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Conference papers on the topic "Stars: individual (Fomalhaut A)"

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Sellgren, K., D. N. B. Hall, S. G. Kleinmann, and N. Z. Scoville. "Kinematics of individual stars in the Galactic Center." In AIP Conference Proceedings Volume 155. AIP, 1987. http://dx.doi.org/10.1063/1.36404.

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Topchieva, A. P. "IR ring nebulae in the Milky Way and M33 galaxies." In Всероссийская с международным участием научная конференция студентов и молодых ученых, посвященная памяти Полины Евгеньевны Захаровой «Астрономия и исследование космического пространства». Ural University Press, 2021. http://dx.doi.org/10.15826/b978-5-7996-3229-8.51.

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Studying the formation of massive stars in our Galaxy and in other galaxies is one of the possibilities to connect the information obtained for the regions of star formation in general. This study presents statistical and theoretical data on infrared ring nebulae (IRRN) in our Galaxy and the galaxy M33, which is located not far from us and in the plane of sky, which is convenient for selecting individual objects. In this paper, comparisons of fluxes for 258 star-forming complexes in M33, extragalactic of star formation complexes, and for IRRN in our Galaxy are shown. A theoretical calculation of the distribution of polycyclic aromatic hydrocarbons using DustEM has been carried out.
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