Redshift distribution of the submillimeter extragalactic background light

The submillimeter (submm) extragalactic background light (EBL) traces the integrated star formation history throughout the cosmic time. Deep blank-field 850 μm and 1.4 GHz surveys and optical follow-up have been only able to determine the redshift of ∼20% of the submm EBL. The majority (80%) of the submm EBL is still below the confusion and sensitivity limits of current submm and radio instruments. We break through these limits with stacking analyses on our deep 850 μm image in the GOODS-N and find that the submm EBL mostly comes from galaxies at redshifts around 1.0. This redshift is much lower than the redshift of z=2–3 previously implied from radio identified submm sources. This result significantly decreases the number of high redshift galaxies that may be seen by ALMA.     

钦州市高温天气气候初探

利用钦州市三站1957～2003年的逐日最高气温资料分析该地高温天气的气候特征,并分析严重高温天气过程的环流背景,总结了严重高温天气过程出现的天气形势特点。结果发现:①钦州市高温天气分布具有较强的地域性和时间性。②中高纬环流平直,西太平洋副热带高压、热带低值系统外围偏北气流的共同作用是严重高温天气过程的天气形势特点。     

平乐县夏季高温干旱天气的天气气候背景分析

对平乐站1957～2003年夏季实况资料进行分析,阐述了当地夏季高温干旱天气分布概况,分析了夏季高温干旱天气的天气背景。     

太原地区灰霾天气特征及影响因子分析

利用2008~2012年太原常规地面气象观测资料、高空探测资料和大气污染物观测资料,对主要天气形势、典型气象要素以及空气污染状况下灰霾天气特征及形成机制进行了综合分析。结果表明:1)太原地区灰霾出现频率存在明显的季节变化,冬半年灰霾出现天数占全年的65.7%;一天中08:00(北京时间,下同)至13:00发生灰霾的频率较高。2)霾日静风频率较高,主导风向为偏东南风;重度灰霾天气出现时相对湿度较高。3)霾日的大气稳定度主要表现为稳定类;霾日平均混合层高度比非霾日低约100 m;08:00逆温出现次数高于20:00,霾时平均逆温强度和厚度高于非霾时。4)高压类型天气形势对灰霾的产生有重要影响,低压天气形势下较少出现灰霾天气。5)可吸入颗粒物、SO2和NO2浓度在非霾日比霾日分别下降32.6%、48.6%、21.7%;随着灰霾等级的增加,SO2和可吸入颗粒物的浓度有显著的增加。6)灰霾天气下到达地面的太阳辐射强度明显减弱,日照时数明显减少。     

鲁西铜石杂岩体边缘物化探特征及找矿前景

归来庄金矿的发现为鲁西地区金矿勘探提供了重要线索,其所在的鲁西铜石杂岩体外围多年来金矿不断突破,随着金矿勘探的进一步需求,本文在成矿地质背景基础上,对研究区进行物探、化探异常查证工作,研究表明研究区Au、Ag异常值较高,伴生元素多为高温热液成矿元素组合,主要分布在研究区断层及断裂带交汇部位,特别是频繁的岩浆活动为金矿的运移和富集创造了条件,为该区金矿勘探指明了方向。     

西秦岭德乌鲁含矿岩体及其包体的岩石学成因和构造意义

德乌鲁岩体位于西秦岭地区,其主体岩性为花岗闪长岩,在岩体内及其接触带发育有多处金、铜矿床。LA-ICP-MS 锆石U-Pb定年表明该岩体侵位于印支早期,年龄为(250±1.8) Ma,该岩体为准铝质,其铝饱和指数ASI为0.9~1.0。所有样品具有高的K2O含量(2.95%~3.52%)、K2O/Na2O比值(0.97~1.10)、Mg#(0.57~0.61)和相容元素含量(w(Cr)=(88~132)×10-6)。因此,我们认为德乌鲁寄主岩形成于壳幔岩浆的混合作用。在该岩体中广泛分布有镁铁质岩浆包体,这些包体即是镁铁质岩浆注入中酸性岩浆中时迅速降温形成的。德乌鲁包体具有中性的成分,其SiO2含量为56.17%~60.95%,岩性主要为辉长闪长岩和闪长岩。相对于寄主岩,包体有着更高的Mg#(0.65~0.67)和低的TiO2含量(0.57%~0.62%)。它们也有着高的钾含量(1.74%~2.43%),属于高钾钙碱性系列岩石。所有样品具有高的相容元素含量,如Cr((212~419)×10-6)和Ni((46~111)×10-6)。相对于重稀土元素,样品中轻稀土元素相对富集,并且具有中等的Eu负异常。在原始地幔标准化的微量元素蛛网图上,所有包体具有明显的Nb-Ta负异常。德乌鲁暗色包体可能形成于曾受俯冲作用改造过的富钾的岩石圈地幔源区部分熔融过程,并伴随有后期镁铁质矿物的分异。本区的印支早期岩浆作用及与其有关的矿床很可能形成于活动大陆边缘环境。     

A double-channel photometer for the Swedish ESO submillimeter telescope

A double channel (1.2 and 2 mm) photometer has been installed at the focus of the 15m SEST antenna in Chile to perform measurements of the Sunyaev-Zeldovich effect towards X-ray ROSAT clusters. This paper describes the instrument and the characteristics of the system: its sensitivity, field of view, noise and the performed calibrations.     

Map-making methods for cosmic microwave background experiments

The map-making step of cosmic microwave background (CMB) data analysis involves linear inversion problems that cannot be performed by a brute-force approach for the large time-lines of today. In this paper we present optimal vector-only map-making methods, which are an iterative COBE method, a Wiener direct filter and a Wiener iterative method. We apply these methods on diverse simulated data, and we show that they produce very well restored maps, by removing nearly completely the correlated noise that appears as intense stripes on the simply pixel-averaged maps. The COBE iterative method can be applied to any signals, assuming the stationarity of the noise in the time-line. The Wiener methods assume both the stationarity of the noise and the sky, which is the case for CMB-only data. We apply the methods to Galactic signals too, and test them on balloon-borne experiment strategies and on a satellite whole-sky survey.     

Application of universal kriging to geochemical prospecting data

In the 1:50,000 mineral-resource assessments for regions of different rock types, the application of universal kriging to process geochemical prospecting data, obtained from different sampling media, can provide much useful information for evaluating mineralization potential. The method has succeeded in effectively separating local anomalies from the regional background, objectively extracting useful information, and improving the analysis of the metallogenic and ore-controlling factors, thereby playing an important role in qualitative and quantitative predictions. In 1:50,000 mineral-resource assessment it is advantageous to use universal kriging in the processing of geochemical prospecting data because universal kriging has many advantages compared to other oreassessment methods.