We present selected results of observations and monitoring of cataclysmic variables (CVs) and related objects by the instruments IBIS and OMC onboard INTEGRAL. We analyse the behaviour of the intermediate polar (IP) V1223 Sgr in a state which we call a shallow low state. We present far X-ray spectra ($E$ up to 60 keV), and the optical and far X-ray orbital modulation. The relation between far X-ray and optical flux appears to be stable over about 400 days. We also present far X-ray observations of some other CVs (or at least upper limits of their far X-ray fluxes) and show that the systems with magnetized white dwarf (like polars and IPs) are observable with INTEGRAL. The OMC light curves show that an outburst and a shallow low state of IX Vel are caused by the mass transfer variations, and not by the thermal instability of the disk, and that the amplitude of the flickering decreases with the decreasing intensity of the “stable” component.

The Deep Impact mission delivered 19 gigajoules of kinetic energy to the nucleus of comet 9P/Tempel 1 on 4 July 2005. Intensive observations, both from the two spacecraft and from Earth and Earth-orbit, while approaching the comet led to numerous new findings about comets. Observations of the impact event, from the flyby spacecraft have led us to a determination of numerous physical properties of the nucleus. Analysis of the near-IR spectra is still very preliminary.

XMM-Newton has observed the quasar 3C273 several times between 2000 June and 2005 July. In addition data of NASA's Rossi X-ray Timing Explorer is used. We present the results of this monitoring campaign.

The X-ray spectrum of 3C273, in the energy regime of 0.2–100 keV, is believed to be composed of three components: a power law component above about 3 keV, a soft excess below about 2 keV, and an Fe-line. The Fe-line, detected in only a few observations of 3C273, is not detected significantly in individual XMM-observations. Only the 2000 June observations show evidence for a presence of a broad line feature. The high energy component above 3 keV is well described by a single power law model with varying indices and fluxes. The steeper spectra show significantly higher flux levels. The soft excess component below 2 keV also shows variations in flux and spectral slope. Different models are tested to identify the soft excess to be thermal or non-thermal emission.

Diffuse clouds are defined as low-density clouds permeated by the ultraviolet interstellar radiation field. We discuss the ensemble of atomic, ionic and molecular observations in the context of our Photon Dominated Region model. The comparison with all observational constraints is limited and implies that the diffuse environment is more complex than originally thought.

Molecular hydrogen is the most abundant molecule in the Universe and dominates the mass budget of the gas, particularly in regions of star formation. H2 is also an important chemical intermediate in the formation of larger species and can be an important gas coolant when the medium lacks metals. Because of the inefficiency of gas-phase reactions to form H2, this molecule is generally thought to form on grain surfaces. Observations of H2 in a wide variety of objects showed that this molecule could form efficiently over a wide range of physical conditions. To understand the mechanism responsible for such an efficient formation, we developed a model for molecular hydrogen formation on grain surfaces. This model considers the interaction between atom and surface as beeing either weak (Van der Waals interaction—physisorption) or strong (covalent bound—chemisorption), as well as the mobility of the atom on a surface due to

quantum mechanical diffusion and thermal hopping. This model solves the time-dependent kinetic rate equation for the formation of molecular hydrogen and its deuterated forms. Our results have been benchmarked with laboratory experiments on silicates, carbonaceous and graphitic surfaces. This comparison allowed us to derive some characteristics of the considered surfaces. An extension of our model to astrophysical conditions gives an estimate of H2 formation efficiency for a wide range of physical conditions. One of our main results is the efficient formation of molecular hydrogen for gas and grain temperatures up to several hundreds of kelvins. We also compared our predictions to observations in astrophysical objects such as photodissociation regions (PDRs). The addition of deuterium in our model for the formation of HD and D2 molecules is also discussed.

ULXs have been studied for 20 years, but only recently have detailed X-ray spectral/timing studies, and investigations of their statistical properties and their environments and counterparts been undertaken. I will review progress in these areas.

In the past several years, great progress has been made on the spectroscopy of polyatomic molecules in diffuse interstellar clouds. In this talk, I will review recent developments involving H$_3^+$, C$_3$, and the Diffuse Interstellar Bands (DIBs).

The simplest polyatomic molecular ion, H$_3^+$, has long been recognized as the cornerstone of ion-neutral chemistry in dense molecular clouds (Herbst & Klemperer 1973; Watson 1973). However, in diffuse clouds (where electrons are abundantly produced from photoionization of atomic carbon) the H$_3^+$ number density was expected to be considerably lower than in dense clouds, owing to the efficiency of electron recombination. It was, therefore, a surprise when a large column density of H$_3^+$ was detected (McCall et al.1998) in the diffuse line of sight towards Cygnus OB2 12, and subsequently in a sample of heavily reddened diffuse sightlines (McCall et al.2002). Recently, we have detected H$_3^+$ even in the classical diffuse cloud sightline towards $\zeta$ Persei; together with a new measurement of the electron recombination rate coefficient, this result suggests that the cosmic-ray ionization rate is much higher in diffuse clouds than in dense clouds (McCall et al. 2003a)!

In 2001, interstellar C$_3$ was first detected by J. P. Maier and colleagues (maier et al. 2001) in three diffuse cloud sightlines. This was quickly followed up by another detection (Roueff et al. 2002) and a survey conducted at low-resolution (Okaet al. 2003). This was followed by a high-resolution survey (Ádámkovics, Blake, & McCall 2003) that yielded rotationally resolved spectra of C$_3$ in 10 sightlines. Much like C$_2$, C$_3$ has no permanent dipole moment, and therefore its rotational distribution serves as a sensitive diagnostic of both temperature and density.

The existence of larger polyatomic molecules in diffuse clouds is clear from the presence of the DIBs, which have remained an enigma since their discovery some eight decades ago. A recent survey of the DIBs at the Apache Point Observatory has resulted in a uniform sample of DIB spectra with much higher signal-to-noise ratios than previously available. Some early results from the analysis of the survey data include the identification of a set of DIBs that are related to C$_2$ (Thorburn et al. 2003) as well as some well-correlated pairs of DIBs. I will discuss our recent results.

The inventory of interstellar and solar system molecules now numbers well over 100 species, including both ions and neutrals. Gas-phase formation routes to many of the observed organics are still uncertain, so that solid-phase syntheses are of interest. Low-temperature reactions are thought to occur within interstellar ices, on ice and grain surfaces in the interstellar medium (ISM), and on icy surfaces of solar system objects (e.g., Europa, Pluto). Ionizing radiation, such as cosmic rays, and far-UV photons are two possible initiators of such chemistry.

In the Cosmic Ice Lab at NASA's Goddard Space Flight Center, we can study both the photo-and radiation-induced chemistries of ices at 8–300 K. Our most-recent work has been motivated by the detections of ethylene glycol, HOCH2CH2OH, in the ISM (Hollis et al. 2002) and in comet Hale-Bopp (Crovisier et al. 2002). Ethylene glycol is currently the largest firmly-identified cometary molecule as well as one of the larger interstellar organics. It's formation and accompanying chemistry provide challenges and tests for current astrochemical thought.

Here we discuss laboratory experiments on ethylene glycol's solid-phase formation and destruction. Using infrared spectroscopy, we have identified low-temperature radiation-chemical pathways that lead from known interstellar ices, such as either CH3OH or H<2O and CO, to ethylene glycol. We also have identified a role for ethylene glycol in the formation of glycolaldehyde, HOCH2C(O)H, a simple sugar (Hollis, Lovas, & Jewell 2000). Related to these results are the 6-and 7-atom molecules formed by oxidation and reduction processes in irradiated H2O + C2H<2 ices. Analogous experiments have been conducted on two other triply-bonded molecules in H<2O-rich ice, HCN and N2. An important focus of our work is the development of reaction schemes for the formation of complex molecules within astrochemically-relevant ices, and the use of such schemes to predict new molecules awaiting detection.

Today's sensitive, high-resolution Chandra X-ray observations allow the study of many populations of X-ray sources. The traditional astronomical tools of photometric diagrams and luminosity functions are now applied to these populations, and provide the means for classifying the X-ray sources and probing their evolution. While overall stellar mass drives the amount of X-ray binaries in old stellar populations, the amount of sources in star forming galaxies is related to the star formation rate. Short-lived, luminous, high mass binaries (HMXBs) dominate these young X-ray populations.

I suggest that stellar coalescence in mid-size protoclusters ($M {\sim} 10^{3.5}$–$10^{4.5} M_{\odot}$) is a possible scenario for the formation of ultraluminous X-ray sources (ULXs). More massive super-star-clusters are not needed, since the most likely ULX mass range is only ${\sim} 30$–$200 M_{\odot}$; in fact, they are very rarely found at or very near ULX positions. Protostellar envelopes and gas accretion favour captures and mergers in dense cores of embedded clusters. Moreover, protoclusters with masses ${\sim} 10^{3.5}$–$10^{4.5} M_{\odot}$ are likely to disperse quickly into loose OB associations, where most ULXs are found. Sufficiently high protostellar density may be achieved when clustered star formation is triggered by galaxy collisions and mergers. Low metallicity may then be necessary to ensure that a large fraction of the stellar mass ends up in a black hole. In this scenario, most ULXs are naturally explained as the extreme end of the high-mass X-ray binary population.

The structure and chemistry of protoplanetary disks depends strongly on the nature of the central star around which it has formed. The dust temperature is mainly set by the stellar luminosity, while the chemistry of the upper disk layers depends on the amount of intercepted UV and X-ray flux. We discuss here the differences in chemistry, thermal structure and line emission around Herbig Ae/Be, T Tauri stars and low-mass M dwarfs. Predictions will be made for future observations with SOFIA and Herschel.

Observations of CO can provide constraints on the density and temperature of the dense star-forming gas in galaxies, while observations of [CI] trace photon-dominated regions and provide information on the amount of atomic carbon in molecular clouds. In this paper, I review CO and [CI] observations of nearby galaxies, with an emphasis on galaxies for which high-resolution observations of multiple transitions and isotopologues are available. I also briefly discuss upper limits on water emission from nearby starburst galaxies and on O2 emission in the SMC obtained with the Odin satellite.

First, the X-ray source populations of M31 and M33 as known from Einstein and ROSAT observations are presented. Then, chandra results on the galaxies are shortly summarized which not only spatially resolved the centre areas but also supernova remnants (SNRs) in both galaxies, and led to source catalogues of restricted areas with high astrometric accuracy. Also luminosity function studies and studies of individual sources based on chandra and XMM-Newton observations led to a better knowledge of the X-ray source populations. After that I will concentrate on XMM-Newton surveys, in which more than 850 and 400 X-ray sources were detected in M31 and M33, respectively, down to a 0.2–4.5 keV luminosity of less than 1035 erg s−1. EPIC hardness ratios as well as informations from earlier X-ray, optical, and radio catalogues were used to distinguish between different source classes (SNRs, supersoft sources (SSSs), X-ray binaries (XRBs), globular cluster sources within the galaxies, and foreground stars, and objects in the background). However, many sources could only be classified as hard.They may either be XRBs or Crab-like SNRs in the galaxies or background sources. Within M31, two globular cluster sources could be identified as low mass XRBs as they showed type I X-ray bursts. Many of the SSSs in both galaxies were identified as optical novae. Due to the high frequency of outbursts in the bulge area of M31 many novae can be monitored at the same time which makes the investigation of class properties much easier compared to novae in the Milky Way or the Magellanic Clouds.

We examine the origin of water in the terrestrial planets. We list various geochemical measurements that may be used to discriminate between different endogenous and exogenous sources of water. Late stage delivery of significant quantities of water from asteroidal and cometary sources appears to be ruled out by isotopic and molecular ratio considerations, unless either comets and asteroids currently sampled spectroscopically and by meteorites are unlike those falling to Earth 4.5 Ga ago or our measurements are not representative of those bodies. The dust in the accretion disk from which terrestrial planets formed was bathed in a gas of H, He and O. The dominant gas phase species were H2O, He, H2O, and CO. Thus grains in the accretion disk must have been exposed to and adsorbed H2 and water. We examine the efficacy of nebular gas adsorption as a mechanism by which the terrestrial planets accreted “wet”. A simple model suggests that grains accreted to Earth could have adsorbed 1 - 3 Earth oceans of water. The fraction of this water retained during accretion is unknown, but these results suggest that at least some of the water in the terrestrial planets may have originated by adsorption.

Until recently hot cores were the first indirect manifestation of a young massive star, but recent observational successes are now providing us with the first candidates for the very early phases of massive star formation, probably the precursors of hot cores. The characteristic hot core chemistry is believed to arise from the evaporation of the icy mantles that accumulate on the dust grains during the collapse the leads to the formation of the massive star. The duration over which the grains are warmed is determined by the time taken for a pre-stellar core to evolve to the Main Sequence. Hence, hot cores and their precursors contain an integrated record of the physics and chemistry occurring during the collapse that led to the star. In this article I will review recent advances in the chemical modelling of hot cores and their precursors in light of the recent TPD experiments on a variety of ices and I will briefly discuss the implications of such studies for the interpretation of high mass protostellar objects.

The SMC is now known to contain many more transient X-ray pulsars than would be expected based on a simple scaling of the number of such sources in the Galaxy by the relative mass of the SMC. We have been conducting regular monitoring observations of the SMC with the Proportional Counter Array on the Rossi X-ray Timing Explorer since 1997. This has resulted in the discovery of many of these X-ray pulsars and also provided orbital period measurements from detections of regular outbursts. We can now investigate the differences and similarities of the Galactic and SMC X-ray pulsar populations and consider the origin of the huge SMC X-ray pulsar over-abundance.

In a subset of the most luminous of the so-called “ultra-luminous” X-ray sources in nearby galaxies, there is evidence for black holes with masses considerably higher than found in Galactic binaries. Apart from extremely high X-ray luminosities, cool disks found in the X-ray spectra of these sources and X-ray timing measurements form the basis for present evidence for intermediate-mass black holes in these sources. New optical and radio measurements appear to support the X-ray evidence. I will review recent X-ray, optical, and radio observations of these ULXs, and discuss the strengths of the intermediate-mass black hole interpretation, arguments against this interpretation, and future prospects for revealing the nature of these ULXS more clearly.

We detail a model we have created to describe the optical emission from a ULX in terms of an irradiated companion star and disk. We apply this model to optical observations of ULX X-7 in NGC 4559. We revise the parameters of the companion star in this system to be older, less massive and of a later spectral type than previously reported. We find the black hole to be of a few hundred solar masses at most.

In the local Universe most massive black holes at the centers of galaxies are not luminous quasars. Is this because (1) they are starved of gas, (2) they accrete without emitting radiation, (3) they refuse to eat, ejecting the incoming material, or (4) they are storing up matter in an accretion disk to feast later?

With Chandra ACIS we have imaged a pilot sample of 6 nearby (D $<$ 30 Mpc) elliptical galaxies chosen to be especially quiescent based on the careful optical spectroscopy of Ho, measured black hole masses (Mbh$\,{>}\,$10(7)Msol), and with existing X-ray upper limits (Lx$\,{<}\,$10(40)erg/s) implying far sub-Eddington accretion. In these galaxies we can measure, or limit, the diffuse hot interstellar medium, and so constrain the Bondi accretion rate.

Faint X-ray emission is detected at or around the nucleus in each galaxy. The morphology of these weak X-ray sources is complex. The X-ray colors of the sources can be determined, and a moderate quality spectrum for one was obtained. We discuss these results against the possible explanations of black hole quiescence.

On the other hand, a few percent of all galaxies shows evidence for nuclear activity and a brief review of the high energy emission from Active Galactic Nuclei is given.

We present optical observations of the newly discovered accretion powered millisecond pulsar IGR J00291+5934, undertaken in the weeks following its outburst on 2$^{nd}$ December 2004. The decay to quiescence is seen to be highly variable with no indication of a modulation on the $\sim$2.46 hr orbital period apparent in the data, consistent with a system at low inclination. We also have a single Keck LRIS spectrum of the companion to IGR J00291+5934 taken 10 days after outburst. Strong hydrogen and helium emission lines are observed confirming the identity of the counterpart.