The way forward

For the last few decades the study of disks around stars young and old and of different types have progressed significantly. During the same time a completely new discipline, the study of exoplanets, planets orbiting stars other than our Sun, have emerged. Both these fields, which are interconnected, have benefited from the development of new instrumentation, and especially by telescopes and detectors deployed in space. In this chapter we are describing the state of the art of such instruments and make an inventory of what is being currently developed. We also state some of the requirements of the next steps and what type of instruments will lead the way forward.Comment: 25 pages, 4 figure

High resolution CO observations of S88-B

CO J = 2-1 and 13CO J = 2-1 and 1-0 observations have been made of the H II region S88-B, using the 15-m James Clerk Maxwell telescope in Hawaii and the 20-m telescope at Onsala. The core of the cloud is resolved into a horseshoelike structure which surrounds a diffuse reflection nebula. The central core has a mass of ≥ 1000 M⊙, with 400 M⊙ in the horseshoe structure. The gas in the horse in the horseshoe appears highly fragmented, and has a kinetic temperature of ≈ 60 K, suggesting it is closely coupled to the dust temperature. A recently formed high mass star appears to be in the process of evacuating a cavity, possibly through a large molecular outflow that is found to show an accelerated component in its blue-shifted lobe. A velocity gradient across the horseshoe structure suggest ordered motion, and could represent rotation in the parental cloud

High signal/noise ¹³CO observations of the bipolar outflow in L1551

New high-signal/noise 13CO observations of the bipolar outflow in the molecular cloud L1551 are reported. Contrary to earlier observations of CO J = 1-0 and 2-1, no strong spatial dependence is found for the velocity profile of these spectra. The implications of these observations are such that the model of an empty shell for this source is less likely, and a model consisting of a shell which contains significant amounts of outflowing molecular gas inside the swept-up cavity walls is suggested

Se människan i var och en av oss! En studie om likabehandling av studenter med annan etnisk bakgrund i högskolan

Syfte Syftet med undersökningen är att upptäcka vilken innebörd som ges åt begreppet likabehandling samt att få fram de uppfattningar som kan finnas i högskolan om likabehandling av studenter med annan etnisk tillhörighet. Dessutom är avsikten att försöka beskriva hur dessa uppfattningar kan påverka i mötet mellan lärare och studenter med annan etnisk bakgrund inom lärarutbildningen. Teori Den fenomenografiska forskningsansatsen med kvalitativa ostrukturerade intervjuer ligger som grund för empirin, med tolkning som instrument. Ett eklektiskt angreppssätt har använts för att försöka förstå komplexiteten i forskningsområdet. Det etnologiska perspektivet försöker förstå och förklara människors tänkesätt och handlingar medan det etnografiska perspektivet som är sprunget ur etnologin, beskriver handlingar och utsagor och hur dessa förändras hela tiden och i olika situationer. Socialpsykologins tredje perspektiv, stämplingsteorin, används som en förklaringsmodell för hur avvikande beteende, utseende och egenskaper används för att dela in människor i olika fack. Metod Trattekniken innebär att intervjun inleds med en öppen övergripande fråga, som i denna studie handlade om fenomenet likabehandling. Intervjuerna fick mer karaktären av samtal, men där studiens fem frågeområden stod i fokus för innehållet. Två pilotintervjuer genomfördes först, och därefter följde ytterligare åtta intervjuer med lärarutbildare och åtta med utländska lärare. Samtliga intervjuer spelades in. Det insamlade materialet har bearbetats i en begreppsanalys och beskrivits i en delvis fenomenografisk modell där begreppen indelats i kategorier. De olika begreppen har bearbetats i flera steg för att försöka nå en metareflektion av innehållet i intervjuerna. Resultat Ett helikopterperspektiv på studiens resultatbeskrivning visar att det som framträder som kontentan av lärarutbildarnas utsagor är begreppen Osäkerhet, Språket och Mötet. De utländska lärarnas utsagor ger andra sammanfattande begrepp, Lika värde, Förutfattade meningar, Annorlundahet och Bortvalda. Det som uppfattas som svårt och problematiskt i mötet mellan lärare och studenter med annan etnisk tillhörighet inom lärarutbildningen verkar inte vara samma sak. Lärarutbildarnas absolut största svårighet att hantera och där flera känner sig provocerade rör svenska språket. Det som är svårast att uppleva för de utländska lärarna är gruppindelningen i olika sammanhang, där de ofta riskerar att bli bortvalda. Bland lärarutbildarna råder ingen enighet om vad likabehandling av studenter i högskolan innebär. Vad det innebär för de utländska lärarna är dock entydigt

Characteristics of proposed 3 and 4 telescope configurations for Darwin and TPF-I

The Darwin and TPF-I missions are Infrared free flying interferometer missions based on nulling interferometry. Their main objective is to detect and characterize other Earth-like planets, analyze the composition of their atmospheres and their capability to sustain life, as we know it. Darwin and TPF-I are currently in study phase. A number of mission architectures of 3 and 4 free flying telescopes are evaluated on the basis of the interferometer's response, ability to distinguish multiple planet signatures and starlight rejection capabilities. The characteristics of the new configurations are compared also to the former, more complex Bowtie baseline architectures as well as evaluated on base of their science capability.Comment: 4 pages, 2 figure

High Angular Resolution, Sensitive CS J=2-1 and J=3-2 Imaging of the Protostar L1551 NE: Evidence for Outflow-Triggered Star Formation ?

High angular resolution and sensitive aperture synthesis observations of CS ($J=2-1$) and CS ($J=3-2$) emissions toward L1551 NE, the second brightest protostar in the Taurus Molecular Cloud, made with the Nobeyama Millimeter Array are presented. L1551 NE is categorized as a class 0 object deeply embedded in the red-shifted outflow lobe of L1551 IRS 5. Previous studies of the L1551 NE region in CS emission revealed the presence of shell-like components open toward L1551 IRS 5, which seem to trace low-velocity shocks in the swept-up shell driven by the outflow from L1551 IRS 5. In this study, significant CS emission around L1551 NE was detected at the eastern tip of the swept-up shell from $V_{\rm{lsr}}$ = 5.3 km s$^{-1}$ to 10.1 km s$^{-1}$, and the total mass of the dense gas is estimated to be 0.18 $\pm$ 0.02 $M_\odot$. Additionally, the following new structures were successfully revealed: a compact disklike component with a size of $\approx$ 1000 AU just at L1551 NE, an arc-shaped structure around L1551 NE, open toward L1551 NE, with a size of $\sim 5000$ AU, i.e., a bow shock, and a distinct velocity gradient of the dense gas, i.e., deceleration along the outflow axis of L1551 IRS 5. These features suggest that the CS emission traces the post-shocked region where the dense gas associated with L1551 NE and the swept-up shell of the outflow from L1551 IRS 5 interact. Since the age of L1551 NE is comparable to the timescale of the interaction, it is plausible that the formation of L1551 NE was induced by the outflow impact. The compact structure of L1551 NE with a tiny envelope was also revealed, suggesting that the outer envelope of L1551 NE has been blown off by the outflow from L1551 IRS 5.Comment: 29 pages, 12 figures, Accepted for Publication in the Astrophysical Journa

The X-ray puzzle of the L1551 IRS 5 jet

Protostars are actively accreting matter and they drive spectacular, dynamic outflows, which evolve on timescales of years. X-ray emission from these jets has been detected only in a few cases and little is known about its time evolution. We present a new Chandra observation of L1551 IRS 5's jet in the context of all available X-ray data of this object. Specifically, we perform a spatially resolved spectral analysis of the X-ray emission and find that (a) the total X-ray luminosity is constant over almost one decade, (b) the majority of the X-rays appear to be always located close to the driving source, (c) there is a clear trend in the photon energy as a function of the distance to the driving source indicating that the plasma is cooler at larger distances and (d) the X-ray emission is located in a small volume which is unresolved perpendicular to the jet axis by Chandra. A comparison of our X-ray data of the L1551 IRS 5 jet both with models as well as X-ray observations of other protostellar jets shows that a base/standing shock is a likely and plausible explanation for the apparent constancy of the observed X-ray emission. Internal shocks are also consistent with the observed morphology if the supply of jet material by the ejection of new blobs is sufficiently constant. We conclude that the study of the X-ray emission of protostellar jet sources allows us to diagnose the innermost regions close to the acceleration region of the outflows.Comment: A&A accepted, 14 pages, 9 figure

The X-ray Luminosities of HH Objects

The recent detection of X-ray emission from HH 2 and HH 154 with the Chandra and XMM-Newton satellites (respectively) have opened up an interesting, new observational possibility in the field of Herbig-Haro objects. In order to be able to plan further X-ray observations of other HH objects, it is now of interest to be able to estimate their X-ray luminosities in order to choose which objects to observe. This paper describes a simple, analytic model for predicting the X-ray luminosity of a bow shock from the parameters of the flow (i.e., the size of the bow shock, its velocity, and the pre-shock density). The accuracy of the analytic model is analyzed through a comparison with the predictions obtained from axisymmetric, gasdynamic simulations of the leading working surface of an HH jet. We find that our analytic model reproduces the observed X-ray luminosities of HH 2 and HH 154, and we propose that HH~80/81 is a good candidate for future observations with Chandra.Comment: 10 pages (8 text, 2 figures