Sparse microgranitoid enclaves (MGE) in the leucocratic I-type Looanga monzogranite near Bendemeer, N.S.W. Australia, range from microdiorite to micromonzogranite and all have fine to medium grainsize igneous microstructures. The enclaves that vary from SiO2 53 to 69 wt.% are all less silicic than the host monzogranite (71-76 wt.%). Although compositionally diverse, the enclaves and host monzogranite pluton share a common mineralogy of quartz, oligodase, ferro-edenitic hornblende, iron-rich (mg similar to 35) biotite, fluor-apatite and +/- K-feldspar. Except for the core of one double enclave, the enclaves have the same Sr-87/Sr-86 initial ratio as the host pluton. A characteristic of the enclaves is high MnO/(MnO + MgO + FeO) ratios with MnO abundances of the more mafic enclaves up to 0.8 wt.%, higher than any common magma The enclaves have a wide range of Na2O/K2O ratios (05 to 2.8) and, in common with the host pluton, contain homblendes with Na2O/K2O ratios varying from 1.5 to 23. The homblendes in two enclaves have lower Na2O/K2O ratios than their host enclave, making it unlikely that the homblende could have crystallised from a melt of the same composition as these enclaves.Chemically and mineralogically the more mafic enclaves have characteristics expected of cumulates formed from a magma of similar composition as the host pluton, in that they contain the same minerals but are enriched in the near-liquidus phases (hornblende, plagioclase and biotite) and depleted in the near-solidus phases (quartz and K-feldspar). Except for some minor replacement of pyroxene by hornblende the minerals do not show microstructural evidence of being made over from other minerals. It is argued that the mineral chemistry of these enclaves is also a primary feature rather than the result of mineralogical equilibration with the host monzogranite magma. The two most felsic enclaves are medium-grained monzogranites (SiO2 68 and 70 wt.%) and are considered to be compositionally little different from the magmas from which they crystallised. These two exhibit hydrothermal alteration and are considered to be fragments of an earlier roof phase of the intrusion.The quench microstructure and cumulate chemistry of the more mafic enclaves are argued to result from P-H2O reduction events within the upper parts of the magma chamber due to roof fracture brought on by the pressure increase imparted to the magma by the fluid release from a water saturated magma The sudden reduction in fluid pressure results in an increase in the liquidus and solidus temperatures of the water saturated magma and this rather than a drop in temperature produces quench conditions. The reduction in No shifts the cotectic compositions in the Q-Ab-Or system closer to K-feldspar and quartz and this and the heat of crystallisation restrict the amount of these two near solidus minerals that crystallise. The enclaves form as crystal cluster cumulates around minerals already in the magma and/or any other solid substrate available including the magma chamber roof. This pressure-quench-cumulate mechanism explains why the Looanga enclaves are mineralogically similar to the host granite and we suggest that this process may be more widely applicable to enclaves in granitic rocks. (C) 2014 Elsevier B.V. All rights reserved.

Zircon Hf isotopic data from six granite supersuites recognised in the New England Batholith of eastern Australia indicate that magma mixing is present in all plutons. Apart from the S-type supersuites, inherited zircons are rare to absent, suggesting that initial melt temperatures were above zircon saturation for the M-, I- and A-type granites. In all supersuites, the range of zircon Hf model ages calculated relative to arc mantle varies greatly, with younger model ages somewhat less than the Permian and Triassic age of crystallisation, and older model ages indicating derivation from source rocks that may be as old as Neoproterozoic. The older model ages are consistent with late Precambrian rocks in the lower crust that may be elements of the Lachlan Fold Belt underlying the New England Fold Belt.Whole-rock delta O-18 and epsilon Nd values, Sr-87/Sr-86 initial ratios (Sr-i) and oxidation state (Fe2O3/FeO) are summarised for the five named supersuites, and for a previously unnamed group of Triassic plutons situated east of the main Batholith for which we propose the name Carrai supersuite. Supersuites with higher delta O-18, higher Sr-i lower delta Li-7 and lower Fe2O3/FeO ratios indicate a metasedimentary component input. The pattern of zircon Hf isotopic variation reflects the other isotopic and geochemical indicators closely, the additional value being that it preserves a magmatic crystallisation record of Hf isotopic variation, that is, a measure of magma mixing from magma generation to final crystallisation. Using the above criteria, at least three distinct crustal components are considered necessary to explain the compositional and isotopic diversity within the Batholith. The crustal components indicated are: 1) a metasedimentary component of Carboniferous and Devonian age for the Hillgrove, Bundarra and Uralla supersuites; 2) a lower crustal K-rich (and Sr-rich) l-type component for the Moonbi, Carrai and possibly Uralla supersuites that could be as old as Proterozoic; and 3) a lower crustal K-poor l-type component of uncertain age for the Clarence River supersuite. In all supersuites, there is strong evidence of an M-type component based on the presence of zircons with high + epsilon Hf values. (C) 2011 Elsevier B.V. All rights reserved.

Following the discovery of the new hard X-ray transient IGR J17511-3057 by INTEGRAL (Atel #2196) and its classification as a millisecond pulsar by RXTE (Atel #2197), a Swift ToO was performed. Swift/XRT observed IGR J17511-3057 on 2009-09-13 at 19:53:31 for a total exposure time of 4 ks. The first 2.5 ks were accumulated in window timing (WT) mode. A thermonuclear type-I X-ray burst was discovered in the WT light curve of the source at 2009-09-14 00:51:37 UTC with an exponential decay time of ~12.5 s.

Supergiant fast X-ray transients (SFXTs) are recently discovered members of the expanding family of high mass X-ray binaries. They represent a population of sources which show transient activity and are associated with blue supergiant optical counterparts. To date INTEGRAL has observed 9 SFXTs; three of which have been conformed to be X-ray pulsars. The fast, transient nature of these sources makes them a challenge to study and understand. Recently, periodic behaviour has been discovered in three such systems and has been attributed to orbital motion. We present here the discovery of a 30 day period in SAX J1818.6-1703.

SAX J1818.6-1703 has been characterized as a supergiant fast X-ray transient system on the basis of several INTEGRAL/IBIS detections since the original BeppoSAX Wide Field Camera detection. Using IBIS/ISGRI, Swift/BAT and archival observations, we show that, in fact, SAX J1818.6-1703 exhibits emission on a period of 30 +/- 0.1 d, with a high degree of recurrence. SAX J1818.6-1703 is therefore the second supergiant fast X-ray transient shown to exhibit periodic outbursts, but with a considerably shorter period than the other known system, IGR J11215-5952.

The timing properties of the 4.45 s pulsar in the Be X-ray binary system GRO J1750-27 are examined using hard X-ray data from INTEGRAL and Swift during a Type II outburst observed during 2008. The orbital parameters of the system are measured and agree well with those found during the last known outburst of the system in 1995. Correcting the effects of the doppler shifting of the period, due to the orbital motion of the pulsar, leads to the detection of an intrinsic spin-up that is well described by a simple model including Pdot and Pdotdot terms of -7.5E-10 ss^-1 and 1E-16 ss^-2 respectively. The model is then used to compare the time-resolved variation of the X-ray flux and intrinsic spin-up against the accretion torque model of Ghosh & Lamb (1979); this finds that GRO J1750-27 is likely located 12-22 kpc distant and that the surface magnetic field of the neutron star is ~2E12 G. The shape of the pulse and the pulsed fraction shows different behaviour above and below 20 keV indicating that the observed pulsations are the convolution of many complex components.

Zircon Hf isotopic data from a zoned pluton of the Moonbi supersuite, New England batholith, eastern Australia, are consistent with magma mixing between two silicic melts, each derived from isotopically distinct sources. Although zircons from three zones within the Walcha Road pluton give a UPb crystallization age of 249 3 Ma, zircon populations from each zone have a range in (Hf). Zircons from the mafic hornblendebiotite monzogranite pluton margin and intermediate zones have (Hf) 5 to 11, whereas those from the more felsic centre of the pluton have (Hf) 7 to 16, representing a total variation of 11 (Hf) units. The LuHf depleted mantle model ages range from 650 to 250 Ma, with the younger zircons present only in the felsic pluton centre. The variation in (Hf) indicates the involvement of silicic melts from at least two sources, one a crustal component with a Neoproterozoic model age and the other a primitive mantle-derived component with model ages similar to the UPb crystallization age of the pluton. The zircons reflect the isotopic compositions of the different proportions of crustal-derived silicic melt, relative to mantle-derived silicic melt, between melt generation and final pluton construction. The Walcha Road pluton is considered to have formed by incremental assembly of progressively more felsic melt batches resulting from mixing, replenishment and crystalmelt separation, with final pluton construction involving mechanical concentration as zones of crystal mush. The zoned pluton and, more broadly, the Moonbi supersuite provide examples of magma mixing by which the more silicic units have more juvenile isotopic compositions as a result of increasing proportions of residual melt from basalt fractionation, relative to crustal partial melt.

INTEGRAL monitoring observations of the Galactic Bulge (e.g. ATels #438 and #1944) have been performed between 2009 Oct 7th 20:29 and 8th 00:11 (UTC) during which transient activity from a few known sources has been recorded with respect to an observation 6 days earlier. The transient low-mass X-ray binary and known X-ray burster GRS 1741.9-2853 (e.g. Cocchi et al. A&A 346, L45, 1999) is detected by INTEGRAL/JEM-X at an average flux of about 58 mCrab (9.3E-10 erg/cm2/s) and 25 mCrab (2.75E-10 erg/ cm2/s) in 3-10 keV and 10-25 keV, respectively.

A new season of observations for the INTEGRAL Galactic Bulge monitoring (see ATel #438) has started on 2009 Feb. 21st. During the latest observation between 2009 Feb 25 13:21 and 17:02 (UT) a type I X-ray burst from SAX J1747.0-2853 (1A 1743-288, aka GX .2-0.2) was detected by JEM-X at UT 14:50:51 (MJD=54887.61865). The burst profile showed clear evidence of a photospheric radius expansion event and the peak flux reached 1.6 Crab (4.2x10-8 erg/cm2/s) in the 3-25 keV range.

During the latest observations of the Galactic Bulge monitoring (see ATel #438), carried out between 2009-09-12 03:21:34 and 2009-09-12 05:27:22 (UTC), INTEGRAL discovered a new bright hard X-ray source, which we designate IGRJ17511-3057. The source is detected in the INTEGRAL/IBIS mosaic image with a significance of 14 sigma in the 20-40 keV energy band, and 7 sigma in the 40-80 keV energy band.

Persistent X-ray activity has been reported by Swift/XRT (ATel #1459) and RXTE/PCA (ATel #1460) from the transient IGR J17473-2721 (= XTE J1747-274; ATels #467, #498) after the detection of an X-ray burst by SuperAGILE (ATel #1445). We report the detection of persistent activity at 18-100 keV with INTERAL/IBIS/ISGRI. The average hard X-ray flux during the Galactic bulge monitoring observations (see ATel #1385) which started on UT 2008 April 1, 16:55 of the source was 41+2 mCrab and 42+3 mCrab, at 18-40 keV and 40-100 keV, respectively, indicating a hard spectral state.

Renewed accretion activity has been reported by Swift/XRT (ATel #1459), XTE/PCA (ATel #1460) and INTEGRAL/IBIS/ISGRI (ATel #1461) from the RXTE transient IGR J17473-2721 (= XTE J1747-274; ATels #467, #498) after the detection of an X-ray burst by SuperAGILE (ATel #1445). From the on- going Galactic bulge monitoring program (see ATels #1385, #1461) we report that the transient continues to brighten as seen with IBIS/ISGRI and JEM-X.

The transient accreting X-ray pulsar GRO J1750-27 (AX J1749.1-2639), which became active end of January 2008 (ATel #1376), has been repeatedly observed by the INTEGRAL Galactic Bulge monitoring program since mid February (ATel #1385) on 11, 20 and 23 Feb. 2008. During the three observations, totalling about 27 ks, the source has remained bright at a roughly constant level with the following flux averaged over the 3 observations: 186+/-9 mCrab (3-10 keV), 319+/-15 mCrab (10-25 keV), 198+/-2 mCrab (18-40 keV), and 20+/-3 mCrab (40-100 keV).

Pulsar systems accelerate particles to immense energies. The detailed functioning of these engines is still poorly understood, but polarization measurements of high-energy radiation may allow us to locate where the particles are accelerated. We have detected polarized gamma rays from the vicinity of the Crab pulsar using data from the spectrometer on the International Gamma-Ray Astrophysics Laboratory satellite. Our results show polarization with an electric vector aligned with the spin axis of the neutron star, demonstrating that a substantial fraction of the high-energy electrons responsible for the polarized photons are produced in a highly ordered structure close to the pulsar.

INTEGRAL Galactic Bulge monitoring (see ATels #438, #874, #1005, #1385) observations on UT 2008 Sep 23 08:51-12:34 reveal a new outburst of the Galactic black-hole candidate and X-ray transient H1743-322/IGR J17464-3213 (see ATels #132, #136, #576, #593, #1348, #1385, #1414). JEM-X and IBIS/ISGRI show a hard X-ray source; the observed fluxes are about 10 mCrab (3-10 keV), 12 mCrab (10-25 keV), 17 mCrab (18-40 keV), and 31 mCrab (40-100 keV).

This is the second paper presenting the results of 2 yr of monitoring of GRS 1915+105 with INTEGRAL, RXTE, and the Ryle Telescope. We present the X-ray spectral and temporal analysis of four observations showing strong radio to X-ray correlations. During one observation GRS 1915+105 was in a steady state, while during the three others it showed cycles of X-ray dips and spikes (followed by radio flares). Through time-resolved spectroscopy of these cycles, we suggest that the soft X-ray spike is the trigger of the ejection. The ejected medium is then the coronal material responsible for the hard X-ray emission. In the steady state observation, the X-ray spectrum is indicative of the hard-intermediate state, with the presence of a relatively strong emission at 15 GHz. The X-ray spectrum is the sum of a Comptonized component and an extra power law extending to energies >200 keV without any evidence for a cutoff. We observe a possible correlation of the radio flux with that of the power law component, which may indicate that we see direct emission from the jet at hard X-ray energies. We study the energy dependence of a ~4 Hz QPO during the hard-intermediate state observation. The QPO ``spectrum'' is well modeled by a power law with a cutoff at an energy of about 11 keV, and clearly differs from the relative contribution of the Comptonized component to the overall flux. This may rule out models of global oscillations of the Compton corona.