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In the Antofagasta Region in northern Chile the large plateau of Chajnantor, located at more than four thousand meters of altitude, has exceptionally clear skies due to the low humidity in the area, allowing for observations in the sub-/millimeter, infrared and optical ranges. In addition, both its easy access through the international road of Paso Jama and its relative isolation from urban centers, make this area an ideal place for astronomical observations. It is in this area where the Atacama Astronomical Park (AAP) is installed, an initiative that seeks to transform the region into a window to the Universe. The AAP is managed by the non-profit Atacama Astronomical Park Foundation, whose board of directors has the power to directly grant an installation permit to projects that present meritorious applications. After some years of operations of astronomical projects at the Park, the AAP is now moving forward with its vision of an integrated support on enabling infrastructure, so the current and future observatories can focus on their core business: to produce Science. The Park identified key strategic areas of support, namely: communications via fiber optics, centralized power solutions, improvement of the access roads, and a corresponding health, safety and security plan. This paper presents the AAP and describes the progress to fulfill the strategic vision of the Atacama Astronomical Park.

We present Spitzer, NIR and millimeter observations of the massive star forming regions W5-east, S235, S252, S254-S258 and NGC7538. Spitzer data is combined with near-IR observations to identify and classify the young population while 12CO and 13CO observations are used to examine the parental molecular cloud. We detect in total 3021 young stellar objects (YSOs). Of those, 539 are classified as Class I, and 1186 as Class II sources. YSOs are distributed in groups surrounded by a more scattered population. Class I sources are more hierarchically organized than Class II and associated with the most dense molecular material. We identify in total 41 embedded clusters containing between 52 and 73% of the YSOs. Clusters are in general non-virialized, turbulent and have star formation efficiencies between 5 and 50%. We compare the physical properties of embedded clusters harboring massive stars (MEC) and low-mass embedded clusters (LEC) and find that both groups follow similar correlations where the MEC are an extrapolation of the LEC. The mean separation between MEC members is smaller compared to the cluster Jeans length than for LEC members. These results are in agreement with a scenario where stars are formed in hierarchically distributed dusty filaments where fragmentation is mainly driven by turbulence for the more massive clusters. We find several young OB-type stars having IR-excess emission which may be due to the presence of an accretion disk., Accepted for publication in MNRAS

A method has been developed for improving both steam injection and production conformance in a thermal EOR project by utilizing intelligent well technology incorporating interval control valves (ICV), well segmentation and associated downhole instrumentation. This provides the ability to selectively open and close segmented sections of the well bore and monitor the key parameters of temperature and pressure from surface. The initial field trial is ongoing in the injector of an Orion field SAGD well pair. Development of the completion system suitable for thermal conditions, initial field trial results and plans for further development are described. Modelling shows that, depending on the level of heterogeneity present in the reservoir, an improvement of 20 to 40% in the steam oil ratio and 5 to10 % in recovery can be achieved in a SAGD process when both improved injection conformance and producer differential steam trap control can be applied in a segmented horizontal well pair. A cost effective solution to achieve this segmentation and control has the potential to add substantial value to field developments through improved steam conformance resulting in increased energy efficiency and oil recovery. The method being developed is applicable to a wide range of EOR processes such as CSS, steam drive and variations. The initial field deployment in the injector well was primarily to prove operability of the system in high temperature thermal applications, to demonstrate the feasibility of modifying steam distribution and to learn for future optimization and deployment of the system. A successful installation and commissioning has substantially validated the completion technology. Early injection test results and data provide a significant improvement in the understanding of the injection and production behavior in the well pair. A test program to optimize the distribution of steam injection in the well is underway and the preliminary results are discussed. Lessons learned from the trial are highlighted. The intelligent completion technology under trial, and proposed further developments, should enable more extensive use of downhole measurement and control in thermal EOR projects to improve performance.

We present Spitzer-IRAC, NOAO 2.1meter-Flamingos, Keck-NIRC, and FCRAO-SEQUOIA observations of the massive star forming complex S254-S258, covering an area of 25x20 arc-minutes. Using a combination of the IRAC and NIR data, we identify and classify the young stellar objects (YSO) in the complex. We detect 510 sources with near or mid IR-excess, and we classify 87 Class I, and 165 Class II sources. The YSO are found in clusters surrounded by isolated YSO in a low-density distributed population. The ratio of clustered to total YSO is 0.8. We identify six new clusters in the complex. One of them, G192.63-00, is located around the ionizing star of the HII region S255. We hypothesize that the ionizing star of S255 was formed in this cluster. We also detect a southern component of the cluster in HII region S256. The cluster G192.54-0.15, located inside HII region S254 has a VLSR of 17 km/s with respect to the main cloud, and we conclude that it is located in the background of the complex. The structure of the molecular cloud is examined using 12CO and 13CO, as well as a near-IR extinction map. The main body of the molecular cloud has VLSR between 5 and 9 km/s. The arc-shaped structure of the molecular cloud, following the border of the HII regions, and the high column density in the border of the HII regions support the idea that the material has been swept up by the expansion of the HII regions., Comment: Accepted for publication in The Astrophysical Journal