Im unternehmerischen Geschäftsverkehr ist die Verwendung von AGB üblich. Laut einer empirischen Untersuchung werden bei jedem fünften Vertrag im unternehmerischen Rechtsverkehr von beiden Vertragsparteien Allgemeine Geschäftsbedingungen (AGB) verwendet. Dabei kommt es häufig vor, dass die AGB kollidieren, denn die Vertragsbedingungen werden nur in den seltensten Fällen miteinander abgestimmt sein. Kommt es sodann in der Vertragsabwicklung zu Schwierigkeiten, gewinnen die AGB erheblich an Bedeutung. Dies Arbeit befasst sich mit den Fragen, ob trotz Kollision ein Vertrag wirksam zustande gekommen ist und welche AGB Vertragsinhalt geworden sind. Hierzu werden die bisherigen Rechtsansichten dargestellt, ein Vergleich mit anderen Rechtsordnungen vorgenommen und ein Ansatz erarbeitet, der sowohl rechtssicher als auch darstellbar ist. Abschließend wird geprüft, inwieweit sich die erarbeitete Lösung auf Sonderprobleme, wie das kaufmännische Bestätigungsschreiben und den Eigentumsvorbehalt, anwenden lässt und zu einer Lösung beiträgt.

The notion that low- to intermediate-mass young stellar objects (YSOs) gain mass at a constant rate during the early stages of their evolution appears to be challenged by observations of YSOs suffering sudden increases of the rate at which they gain mass from their circumstellar discs. Also, this idea that stars spend most of their lifetime with a low accretion rate and gain most of their final mass during short-lived episodes of high accretion bursts, helps to solve some long-standing problems in stellar evolution. The original classification of eruptive variables divides them in two separate subclasses known as FU Orionis stars (FUors) and EX Lupi stars (EXors). In this classical view FUors are at an early evolutionary stage and are still gaining mass from their parent envelopes, whilst EXors are thought to be older objects only surrounded by an accretion disc. The problem with this classical view is that it excludes younger protostars which have higher accretion rates but are too deeply embedded in circumstellar matter to be observed at optical wavelengths. Optically invisible protostars have been observed to display large variability in the near-infrared. These and some recent discoveries of new eruptive variables, show characteristics that can be attributed to both of the optically-defined subclasses of eruptive variables. The new objects have been proposed to be part of a new class of eruptive variables. However, a more accepted scenario is that in fact the original classes only represent two extremes of the same phenomena. In this sense eruptive variability could be explained as arising from one physical mechanism, i.e. unsteady accretion, where a variation in the parameters of such mechanism can cause the different characteristics observed in the members of this class. With the aim of studying the incidence of episodic accretion among young stellar objects, and to characterize the nature of these eruptive variables we searched for high amplitude variability in two multi-epoch infrared surveys: the UKIDSS Galactic Plane Survey (GPS) and the Vista Variables in the Via Lactea (VVV). In order to further investigate the nature of the selected variable stars, we use photometric information arising from public surveys at near- to farinfrared wavelengths. In addition we have performed spectroscopic and photometric follow-up for a large subset of the samples arising from GPS and VVV. We analyse the widely separated two-epoch K-band photometry in the 5th, 7th and 8th data releases of the UKIDSS Galactic Plane Survey. We find 71 stars with _K > 1 mag, including 2 previously known OH/IR stars and a Nova. Even though the mid-plane is mostly excluded from the dataset, we find the majority (66%) of our sample to be within known star forming regions (SFRs), with two large concentrations in the Serpens OB2 association (11 stars) and the Cygnus-X complex (27 stars). The analysis of the multi-epoch K-band photometry of 2010-2012 data from VVV covering the Galactic disc at |b| < 1◦ yields 816 high amplitude variables, which include known variables of different classes such as high mass X-ray binaries, Novae and eclipsing binaries among others. Remarkably, 65% of the sample are found concentrated towards areas of star formation, similar to the results from GPS. In both surveys, sources in SFRs show spectral energy distributions (SEDs) that support classification as YSOs. This indicates that YSOs dominate the Galactic population of high amplitude infrared variable stars at low luminosities and therefore likely dominate the total high amplitude population. Spectroscopic follow-up allows us to confirm the pre-main sequence nature of several GPS and VVV Objects. Most objects in both samples show spectroscopic signatures that can be attributed to YSOs undergoing high states of accretion, such as veiling of photospheric features and CO emission, or show FUor-like spectra. We also find a large fraction of objects with 2.12 μm H2 emission that can be explained as arising from shock-excited emission caused by molecular outflows. Whether these molecular outflows are related to outbursts events cannot be confirmed from our data. Adding the GPS and VVV spectroscopic results, we find that between 6 and 14 objects are new additions to the FUor class from their close resemblance to the near-infrared spectra of FUors, and at least 23 more objects are new additions to the eruptive variable class. For most of these we are unable to classify them into any of the original definitions for this variable class. In any case, we are adding up to 37 new stars to the eruptive variable class which would double the current number of known objects. We note that most objects are found to be deeply embedded optically invisible stars, thus increasing the number of objects belonging to this subclass by a much larger factor. In general, objects in our samples which are found to be likely eruptive variable stars show a mixture of characteristics that can be attributed to both of the optically-defined classes. This agrees well with the recent discoveries in the literature. Finally, we are able to derive a first rough estimate on the incidence of episodic accretion among class I YSOs in the star-forming complex G305. We find that _ 9% of such objects are in a state of high accretion. This number is in agreement with previous theoretical and observational estimates among class I YSOs.

In this thesis, I present the properties of IRAS 19306+1407 central source and its sur- rounding circumstellar envelope (CSE), from the analysis of near-infrared (near-IR) polarimetry and integral field spectroscopy (IFS), with supporting archived HST im- ages and sub-millimetre (sub-mm) photometry. This is supported by axi-symmetric light scattering (ALS), axi-symmetric radiative transfer (DART) and molecular hy-drogen (H2) shock models. The polarimetric images show that IRAS 19306+1407 has a dusty torus, which deviates from axisymmetry and exhibits a ‘twist’ feature. The DART and ALS modelling shows that the CSE consists of Oxygen-rich sub-micrometre dust grains, with a range in temperature from 130±30 to 40±20 K at the inner and outer radius, respectively, with inner and outer radii of 1.9±0.1×1014 and 2.7±0.1×1015 m. The CSE detached 400±10 years ago and the mass loss lasted 5700±160 years, assuming a constant asymptotic giant branch (AGB) outflow speed of 15 km s−1. The dust mass and total mass of the CSE is 8.9±5×10−4 and 1.8±1.0×10 −1 M⊙, assuming a gas-to-dust ratio of 200. The mass loss rate was 3.4±2.1×10−5 M⊙ year−1. The central source is consistent with a B1I-type star with a radius of 3.8 ± 0.6 R⊙, luminosity of 4500 ± 340 L⊙ at a distance of 2.7 ± 0.1 kpc. A purpose built idl package (fus) was developed and used in the SINFONI IFS data critical final reduction steps. It also produced emission line, kinematic and line ratio images. The IFS observations show that H2 is detected throughout the CSE, located in bright arcs and in the bipolar lobes. The velocity of the H2 is greatest at the end of the lobes. Brγ emission originates from, or close, to the central source – produced by a fast jump (J) shock or photo-ionised atomic gas. The 1-0 S(1)/2- 1 S(1) and 1-0 S(1)/3-2 S(3) ratios were used as a diagnostic and determined that H2 was excited by bow shaped shocks; however, these shock models could not wholly explain the observed rotational and vibrational temperatures. The CDR values were fitted by combining continuous (C) or J-bow shock and fluorescence models, with a contribution from the latter, observed throughout the CSE (5–77 per cent). The majority of shock can be described by a C-bow shock model with B = 0.02 to 1.28 mG. Shocks are predominately seen in the equatorial regions. Polarimetry and IFS highlight a ‘twist’ feature, which could be due to an episodic jet undergoing a recent change in the outflow direction. The sub-arcsecond IFS observations reveal a flocculent structure in the south- east bright arc, consisting of several clumps interpreted as a fast-wind eroding an equatorial torus, possibly forming H2 knots seen in (some) evolved planetary nebulae (PNe). My analysis has effectively constrained the following: spectral type, stellar radius, luminosity and distance, chemistry, dust grain properties, geometry, age, mass loss, excitation mechanism and evolutionary state of the post-AGB star and its surrounding CSE. I conclude that IRAS 19306+1407 is a post-AGB object on the verge becoming a PN.

<p>A major fraction of stars will pass through a short period of dramatic events in their final evolutionary stage. Low- to intermediate-mass stars, studied here, are stripped of their outer parts in a slow massive wind. This mass loss reshapes both the star and the surrounding medium. The formation of the wind is a consequence of the non-linear interaction of a number of physical processes. Stellar pulsations and efficient dust formation are examples of such key processes. Time-dependent theoretical models, in combination with observations, are useful tools for understanding these winds.</p><p>The main object of this thesis has been the physical improvement of a theoretical wind model. Here the coupling between the dust and gas in the wind is studied in further detail, allowing drift. The methods that have been developed earlier to describe the micro-physical interaction are overviewed and summarized. Previously dust has often been assumed to move at the same velocity as gas. New time-dependent wind models are presented where grain drift has been treated self-consistently. Specifically, the coupling between dust and gas in the wind has been modeled more realistically, with descriptions of both the modified momentum and energy balances, and drift dependent dust formation. The results of these new ``drift models'' have been compared with the results of non-drift models. </p><p>A general result of the study is that the effects of drift are significant and difficult to predict if a simple analytical theory is used. It has been found that dust in drift models tends to accumulate in certain dense regions, an accumulation that was not possible without drift. Moreover the new models show an increased variability in the wind structure. The use of drift in dust formation tends to markedly increase the produced dust. Some sets of model parameters lead to a wind without including drift, but a corresponding wind does not form when drift is included -- and vice versa. The effects of drift are important and can probably not be ignored in realistic models.</p>

Central stars of planetary nebulae are low-mass stars on the brink of their final evolution towards white dwarfs. Because of their surface temperature of above 25,000 K their UV radiation ionizes the surrounding material, which was ejected in an earlier phase of their evolution. Such fluorescent circumstellar gas is called a "Planetary Nebula". About one-tenth of the Galactic central stars are hydrogen-deficient. Generally, the surface of these central stars is a mixture of helium, carbon, and oxygen resulting from partial helium burning. Moreover, most of them have a strong stellar wind, similar to massive Pop-I Wolf-Rayet stars, and are in analogy classified as [WC]. The brackets distinguish the special type from the massive WC stars. Qualitative spectral analyses of [WC] stars lead to the assumption of an evolutionary sequence from the cooler, so-called late-type [WCL] stars to the very hot, early-type [WCE] stars. Quantitative analyses of the winds of [WC] stars became possible by means of computer programs that solve the radiative transfer in the co-moving frame, together with the statistical equilibrium equations for the population numbers. First analyses employing models without iron-line blanketing resulted in systematically different abundances for [WCL] and [WCE] stars. While the mass ratio of He:C is roughly 40:50 for [WCL] stars, it is 60:30 in average for [WCE] stars. The postulated evolution from [WCL] to [WCE] however could only lead to an increase of carbon, since heavier elements are built up by nuclear fusion. In the present work, improved models are used to re-analyze the [WCE] stars and to confirm their He:C abundance ratio. Refined models, calculated with the Potsdam WR model atmosphere code (PoWR), account now for line-blanketing due to iron group elements, small scale wind inhomogeneities, and complex model atoms for He, C, O, H, P, N, and Ne. Referring to stellar evolutionary models for the hydrogen-deficient [WC] stars, Ne and N abundances are of particular interest. Only one out of three different evolutionary channels, the VLTP scenario, leads to a Ne and N overabundance of a few percent by mass. A VLTP, a very late thermal pulse, is a rapid increase of the energy production of the helium-burning shell, while hydrogen burning has already ceased. Subsequently, the hydrogen envelope is mixed with deeper layers and completely burnt in the presence of C, He, and O. This results in the formation of N and Ne. A sample of eleven [WCE] stars has been analyzed. For three of them, PB 6, NGC 5189, and [S71d]3, a N overabundance of 1.5% has been found, while for three other [WCE] stars such high abundances of N can be excluded. In the case of NGC 5189, strong spectral lines of Ne can be reproduced qualitatively by our models. At present, the Ne mass fraction can only be roughly estimated from the Ne emission lines and seems to be in the order of a few percent by mass. Furthermore, using a diagnostic He-C line pair, the He:C abundance ratio of 60:30 for [WCE] stars is confirmed. Within the framework of the analysis, a new class of hydrogen-deficient central stars has been discovered, with PB 8 as its first member. Its atmospheric mixture resembles rather that of the massive WNL stars than of the [WC] stars. The determined mass fractions H:He:C:N:O are 40:55:1.3:2:1.3. As the wind of PB 8 contains significant amounts of O and C, in contrast to WN stars, a classification as [WN/WC] is suggested. / Zentralsterne Planetarischer Nebel sind massearme Sterne kurz vor ihrer finalen Entwicklung zu Weißen Zwergen. Aufgrund ihrer Oberflächentemperatur von über 25 000 K sind sie in der Lage, durch Abstrahlung von UV-Licht das sie umgebende Material, welches in einer vorigen Phase ihrer Entwicklung abgestoßen wurde, zu ionisieren. Das solchermaßen zum Leuchten angeregte Gas bezeichnet man als Planetarischen Nebel. Etwa ein Zehntel der galaktischen Zentralsterne sind wasserstoffarm. Im Allgemeinen besteht die Oberfläche dieser Zentralsterne aus einer Mischung der Elemente Helium, Kohlenstoff und Sauerstoff, welche z.T. durch Heliumbrennen erzeugt wurden. Die meisten dieser Sterne haben darüberhinaus einen starken Sternwind, ähnlich den massereichen Pop-I-Wolf-Rayet-Sternen und werden in Analogie zu diesen als [WC] klassifiziert, wobei die eckigen Klammern der Unterscheidung von den massereichen WC-Sternen dienen. Qualitative Analysen der Spektren von [WC]-Sternen lassen eine Entwicklungssequenz dieser Sterne von kühleren sogenannten late-type [WC]-Sternen (kurz [WCL]) zu sehr heißen, early-type [WC]-Sternen (kurz [WCE]) vermuten. Mithilfe von Computerprogrammen, die den Strahlungstransport im mitbewegten Beobachtersystem zusammen mit den statistischen Gleichungen der Besetzungszahlen der Ionen im Sternwind rechnen können, wurden quantitative Untersuchungen der Winde von [WC]-Sternen möglich. Erste Analysen mit Modellen ohne Eisenlinien ergaben dabei systematisch unterschiedliche Häufigkeiten für [WCL]- und [WCE]-Sterne. Während sich für [WCL]-Sterne ein Verhältnis der Massenanteile von He:C von etwas 40:50 ergab, fand man für die [WCE]-Sterne ein mittleres Verhältnis von 60:30 für die He:C-Massenanteile. Dabei sollte die Entwicklung von [WCL] nach [WCE] innerhalb einer sehr kurzen Zeit durch Aufheizung infolge der Kontraktion der Hülle erfolgen und nicht mit einer wesentlichen Abnahme der Kohlenstoffhäufigkeit bei gleichzeitiger Zunahme der Heliumhäufigkeit an der Oberfläche einhergehen. Im Rahmen der vorgelegten Arbeit wird untersucht, ob sich mittels verbesserter Modelle für die Atmosphären von [WC]-Sternen das He:C-Häufigkeitsverhältnis der [WCE]-Sterne bestätigt. Elaboriertere Modelle, welche vom Potsdamer WR-Modelatmosphären-Code (PoWR) berechnet werden können, berücksichtigen Line-Blanketing aufgrund von Elementen der Eisengruppe, kleinskalige Windinhomogenitäten und die Elemente He, C, O, H, P, N und Ne. Unter Bezug auf Sternentwicklungsmodelle, die die Ursache der Wasserstoffunterhäufigkeit von [WC]-Sternen erklären, sind insbesondere die Neon- und Stickstoff-Häufigkeiten interessant. Von den drei möglichen Entwicklungskanälen für [WC]-Sterne führt lediglich das VLTP-Szenario zu einer Stickstoff-Überhäufigkeit von einigen Prozent bezogen auf die Masse. Bei einem VLTP, einem very late thermal pulse, handelt es sich um einen plötzlichen, starken Anstieg der Energieproduktion in der helium-brennenden Schale, während das Wasserstoffbrennen bereits zum Erliegen gekommen ist. Infolge eines VLTPs wird sämtlicher Wasserstoff kurz nach dem thermischen Puls in tiefere Schichten gemischt und in Anwesenheit von C, He und O verbrannt. Infolgedessen wird N und auch Ne erzeugt. Bei der Analyse von elf [WCE]-Sternen wurden für drei von ihnen, PB 6, NGC 5189 und [S71d]3, Stickststoffmassenanteile von 1,5 % bestimmt, während für drei andere Sterne solche hohen Stickstoffhäufigkeiten ausgeschlossen werden können. Für NGC 5189 gelang außerdem die qualitative Reproduktion der beobachteten, starken Ne-Spektrallinien mittels unserer Modelle. Zur Zeit lässt sich aus der Stärke der Ne-Emissionslinien der Ne-Massenanteil leider nur abschätzen, er scheint aber im Bereich einiger Prozent zu liegen. Mittels eines diagnostischen He-C-Linienpaares konnte das He:C-Massenverhältnis von 60:30 für [WCE]-Sterne bestätigt werden. Als Ergebnis der Analyse von PB 8 postulieren wir eine neue Klasse von wasserstoffarmen Zentralsternen, die in ihrer Elementzusammensetzung eher an massereiche WNL-Sterne als an [WC]-Sterne erinnern. Die ermittelten Massenanteile H:He:C:N:O betragen 40:55:1.3:2:1.3, der Wind von PB 8 enthält daher im Unterschied zu WN-Sternen signifikante Mengen von O und C. Es wird daher eine Klassifizierung als [WN/WC] vorgeschlagen.

A major fraction of stars will pass through a short period of dramatic events in their final evolutionary stage. Low- to intermediate-mass stars, studied here, are stripped of their outer parts in a slow massive wind. This mass loss reshapes both the star and the surrounding medium. The formation of the wind is a consequence of the non-linear interaction of a number of physical processes. Stellar pulsations and efficient dust formation are examples of such key processes. Time-dependent theoretical models, in combination with observations, are useful tools for understanding these winds. The main object of this thesis has been the physical improvement of a theoretical wind model. Here the coupling between the dust and gas in the wind is studied in further detail, allowing drift. The methods that have been developed earlier to describe the micro-physical interaction are overviewed and summarized. Previously dust has often been assumed to move at the same velocity as gas. New time-dependent wind models are presented where grain drift has been treated self-consistently. Specifically, the coupling between dust and gas in the wind has been modeled more realistically, with descriptions of both the modified momentum and energy balances, and drift dependent dust formation. The results of these new ``drift models'' have been compared with the results of non-drift models. A general result of the study is that the effects of drift are significant and difficult to predict if a simple analytical theory is used. It has been found that dust in drift models tends to accumulate in certain dense regions, an accumulation that was not possible without drift. Moreover the new models show an increased variability in the wind structure. The use of drift in dust formation tends to markedly increase the produced dust. Some sets of model parameters lead to a wind without including drift, but a corresponding wind does not form when drift is included -- and vice versa. The effects of drift are important and can probably not be ignored in realistic models.

No description available.

Polarization is a powerful tool for understanding stellar atmospheres and circumstellar environments. Mira and semi-regular variable stars have been observed for decades and some are known to be polarimetrically variable, however, the semi-regular variable V Canes Venatici displays an unusually large, unexplained amount of polarization. We present ten years of optical polarization observations obtained with the HPOL instrument, supplemented by published observations spanning a total interval of about forty years for V CVn. We find that V CVn shows large polarization variations ranging from 1 - 6%. We also find that for the past forty years the position angle measured for V CVn has been virtually constant suggesting a long-term, stable, asymmetric structure about the star. We suggest that this asymmetry is caused by the presence of a stellar wind bow shock and tail, consistent with the star's large space velocity.

Since the identi cation of proto-planetary nebulae (PPNe) as transition objects between the asymptotic giant branch stars and planetary nebulae more than two decades ago, astronomers have attempted to characterise these exciting objects. Today many questions still elude a conclusive answer, partly due to the sheer diversity observed within this small subset of stellar objects, and partly due to the low numbers detected. Fortunately, many of these objects display a rich spectrum of emission/absorption lines that can be used as diagnostics for these nebulae. This dissertation presents a study of six PPNe using the relatively new (at NIR wavelengths) integral eld spectroscopy technique. This method has allowed the investigation of distinct regions of these nebulae, and in certain cases the application of magneto-hydrodynamic shock models to the data. The goal of this research has been to investigate the evolution of PPNe by detailed examination of a small sample of objects consisting of a full range of evolutionary types. Near-IR ro-vibrational lines were employed as the primary tool to tackle this problem. In all six sources the 1!0S(1) line is used to map the spatial extent of the H2. In three of these objects the maps represent the rst images of their H2 emission nebulae. In the case of the earliest-type object (IRAS 14331-6435) in this sample, the line map gives the rst image of its nebula at any wavelength. In the only M-type object (OH 231.8+4.2) in the sample, high-velocity H2 is detected in discrete clumps along the edges of the bipolar out ow, while a possible ring of slower moving H2 is found around the equatorial region. This is the rst detection of H2 in such a late-type object but due its peculiarities, it is possibly not representative of what is expected of M-type objects. In IRAS 19500-1709, an intermediate-type object, the line map shows the H2 emission to originate in clumpy structures along the edges of a bipolar shell/out ow. The remaining three objects have all been the subject of previous studies but in each case new H2 lines are detected in this work along with other emission lines (Mg ii, Na i &amp; CO). In the case of IRAS 16594-4656, MHD shock models have been used to determine the gas density and shock velocity. Two new python modules/classes have been written. The rst one to deal with the data cubes, extract ux measurements, rebin regions of interest, and produce line maps. The second class allows the easy calculation of many important parameters, for example, excitation temperatures, column density ratio values, extinction estimates from several line-pairs, column density values, and total mass of the H2. The class also allows the production of input les for the shock tting procedure, and simulated shocks for testing this tting process. A new framework to t NIR shock models to data has been developed, employing Monte Carlo techniques and the extensive computing cluster at the University of Hertfordshire (UH). This method builds on the approach used by many other authors, with the added advantages that this framework provides a method of correctly sampling the shock model parameter space, and providing error estimates on the model t. Using this approach, data from IRAS 16594-4656 have been successfully modelled using the shock models. A full description of this class of stellar objects from such a small sample is not possible due to their diverse nature. Although H2 was detected across the full spectral vi range of post-AGB objects, the phase at which H2 emission begins is still not clear. The only M-type object in this work is a peculiar object and may not be representative of a typical post-AGB star. The H2 PPNe appear to be located at lower Galactic latitudes (b 20 ) than the total PPNe population, possibly pointing to an above average mass and hence younger age of these objects.

In this study we present photometric predictions for C-type Asymptotic Giant Branch Stars (AGB) stars from Eriksson et al. (2014) for the James Webb Space Telescope (JWST) and the Wide-field Infrared Survey Explorer (WISE) instruments. The photometric predictions we have done are for JWST’s general purpose wide-band filters on NIRCam and MIRI covering wavelengths of 0.7 — 21 microns. AGB stars contribute substantially to the integrated light of intermediate-age stellar popula- tions and is a substantial source of the metals (especially carbon) in galaxies. Studies of AGB stars are (among other reasons) important for the understanding of the chemical evolution and dust cycle of galaxies. Since the JWST is scheduled for launch in 2018 it should be a high priority to prepare observing strategies. With these predictions we hope it will be possible to optimize observing strategies of AGB stars and maximize the science return of JWST. By testing our method on Whitelock et al. (2006) objects from the WISE catalog and comparing them with our photometric results based on Eriksson et al. (2014) we have been able to fit 20 objects with models. The photometric data set can be accessed at: http://www.astro.uu.se/AGBmodels/ / I den här studien har jag gjort fotometriska förutsägelser för asymptotis- ka jättegrensstjärnor (AGB-stjärnor) av C typ från Eriksson et al. (2014) modifierade för instrument ombord på James Webb Space Telescope (JWST) och Wide-field Infrared Survey Explorer (WISE). AGB-stjärnor bidrar kraftigt till det totala ljuset av stjärnor av intermediär ålder och är också en stor källa till metaller (speciellt kol) i galaxer. Studier av AGB stjärnor är viktiga av flera anledningar, däribland för att förstå den kemiska evolutionen och stoftcykler i galaxer. JWST är planerad att skjutas upp 2018 och fram till dess bör det vara en hög prioritet att förbereda observeringsstrategier. Med den fotometriska datan i den här studien hoppas vi att användare av JWST kommer kunna optimera sina observeringsstrategier av AGB-stjärnor och få ut så mycket som möjligt av sin obseravtionstid med teleskopet. Vi har testat metoden genom att titta på objekt från Whitelock et al. (2006) i WISE-katalogen och jämföra dem med de fotometriska resultaten baserade på modellerna från Eriksson et al. (2014). På detta sett har vi lyckats matcha 20 objekt med modeller. Den fotometriska datan går att ladda ner ifrån: http://www.astro.uu.se/AGBmodels/