A new catalytic oxidation using 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) and NaClO is applied to hardwood cellulose in water at 60 °C and pH 6.8 with NaClO(2) used as a primary oxidant. The oxidized celluloses with carboxylate content of approximately 0.8 mmol/g were convertible to highly crystalline and individual fibrils 5 nm in width and at least 2 μm in length by disintegration in water. The oxidized celluloses had no aldehyde groups, and high degrees of polymerization of more than 900. Solid-state (13)C NMR and X-ray analyses revealed that the C6 carboxylate groups formed are selectively present on the crystalline fibril surfaces at high densities. Films prepared from the dispersions were transparent and flexible, and exhibited a high tensile strength of 312 MPa even at a low density of 1.47 g/cm(3).

Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2m Subaru telescope on the summit of Maunakea in Hawaii. A team of scientists from Japan, Taiwan and Princeton University is using HSC to carry out a 300-night multi-band imaging survey of the high-latitude sky. The survey includes three layers: the Wide layer will cover 1400 deg 2 in five broad bands (grizy), with a 5 σ point-source depth of r ≈ 26. The Deep layer covers a total of 26 deg 2 in four fields, going roughly a magnitude fainter, while the UltraDeep layer goes almost a magnitude fainter still in two pointings of HSC (a total of 3.5 deg 2). Here we describe the instrument, the science goals of the survey, and the survey strategy and data processing. This paper serves as an introduction to a special issue of the Publications of the Astronomical Society of Japan, which includes a large number of technical and scientific papers describing results from the early phases of this survey.

We present the most extensive combined photometric and spectroscopic study to date of the enormous globular cluster (GC) system around M87, the central giant elliptical galaxy in the nearby Virgo cluster. Using observations from DEIMOS and LRIS at Keck, and Hectospec on the MMT, we derive new, precise radial velocities for 451 GCs around M87, with projected radii from ∼ 5 to 185 kpc. We combine these measurements with literature data for a total sample of 737 objects, which we use for a re-examination of the kinematics of the GC system of M87. The velocities are analyzed in the context of archival wide-field photometry and a novel Hubble Space Telescope catalog of half-light radii, which includes sizes for 344 spectroscopically confirmed clusters. We use this unique catalog to identify 18 new candidate ultra-compact dwarfs, and to help clarify the relationship between these objects and true GCs.We find much lower values for the outer velocity dispersion and rotation of the GC system than in earlier papers, and also differ from previous work in seeing no evidence for a transition in the inner halo to a potential dominated by the Virgo cluster, nor for a truncation of the stellar halo. We find little kinematical evidence for an intergalactic GC population. Aided by the precision of the new velocity measurements, we see significant evidence for kinematical substructure over a wide range of radii, indicating that M87 is in active assembly. A simple, scale-free analysis finds less dark matter within ∼ 85 kpc than in other recent work, reducing the tension between X-ray and optical results. In general, out to a projected radius of ∼ 150 kpc, our data are consistent with the notion that M87 is not dynamically coupled to the Virgo cluster; the core of Virgo may be in the earliest stages of assembly.29 These four GCs are S279, S348, S501, and VUCD10. The fifth, S1265, has a normal GC size, and is the closest of the five objects to vsys, but intriguingly has a very similar distance, color, magnitude, and velocity to the bona fide UCD S1629. Also, two bright transition objects that fit the same pattern are S77 and S137, which have similar positions, velocities (from Cohen 2000 andHanes et al. 2001), colors, magnitudes, and sizes to each other. These seem likely to share a common origin.

We present the results of a deep, wide-area, optical and near-IR survey of massive high-redshift galaxies. The Prime Focus Camera (Suprime-Cam) on the Subaru telescope was used to obtain BRIz ′ imaging over 2 × 940 arcmin 2 fields, while JK s imaging was provided by the SOFI camera at the New Technology Telescope (NTT) for a subset of the area, partly from the ESO Imaging Survey (EIS). In this paper, we report on the properties of K-band-selected galaxies, identified from a total area of ∼ 920 arcmin 2 to K Vega = 19, of which 320 arcmin 2 are complete to K Vega = 20. The BzK selection technique was used to assemble complete samples of about 500 candidate massive star-forming galaxies (sBzKs) and about 160 candidate massive passively evolving galaxies (pBzKs) at 1.4 < ∼ z < ∼ 2.5; and the (R − K) Vega > 5 color criterion was used to assemble a sample of about 850 extremely red objects (EROs). We accurately measure surface densities of 1.20 ± 0.05 arcmin −2 and 0.38 ± 0.03 arcmin −2 for the sBzKs and the pBzKs, respectively. Both sBzKs and pBzKs are strongly clustered, at a level at least comparable to that of EROs, with pBzKs appearing more clustered than sBzKs. We estimate the reddening, star formation rates (SFRs) and stellar masses (M * ) for the ensemble of sBzKs, confirming that to K Vega ∼ 20 typical (median) values are M * ∼ 10 11 M ⊙ , SFR ∼ 190 M ⊙ yr −1 , and E(B − V ) ∼ 0.44. A correlation is detected such that the most massive galaxies at z ∼ 2 are also the most actively star-forming, an effect that can be seen as a manifestation of downsizing at early epochs. The space density of massive pBzKs at z ∼ 1.4 − 2 that we derive is 20%±7% that of similarly massive early-type galaxies at z ∼ 0. Adding this space density to that of our massive star forming class, sBzKs, in the same redshift range produces a closer comparison with the local early-type galaxy population, naturally implying that we are detecting star formation in a sizable fraction of massive galaxies at z > 1.4, which has been quenched by the present day. Follow-up optical and near infrared spectroscopy is in progress at the ESO Very Large Telescope (VLT) and at the Subaru telescope, in order to elucidate more thoroughly the formation and evolution of massive galaxies. 3 The relevant conversions between Vega and AB magnitudes for this paper are B AB = B Vega − 0.08, R AB = R Vega + 0.22, z AB = z Vega + 0.53, and K AB = K Vega + 1.87.

We report the ultraviolet luminosity function (UVLF) of Lyman break galaxies at z∼ 5 derived from a deep and wide survey using the prime focus camera of the 8.2 m Subaru telescope (Suprime‐Cam). Target fields consist of two blank regions of the sky, namely, the region including the Hubble Deep Field‐North and the J0053+1234 region, and the total effective surveyed area is 1290 arcmin2. Applications of carefully determined colour selection criteria in V−Ic and Ic−z′ yield a detection of 853 z∼ 5 candidates with z′AB < 26.5 mag. The UVLF at z∼ 5 based on this sample shows no significant change in the number density of bright (L≳L*z=3) LBGs from that at z∼ 3, while there is a significant decline in the LF's faint end with increasing look‐back time. This result means that the evolution of the number densities is differential with UV luminosity: the number density of UV luminous objects remains almost constant from z∼ 5 to 3 (the cosmic age is about 1.2 to 2.1 Gyr) while the number density of fainter objects gradually increases with cosmic time. This trend becomes apparent thanks to the small uncertainties in number densities both in the bright and faint parts of LFs at different epochs that are made possible by the deep and wide surveys we use. We discuss the origins of this differential evolution of the UVLF along the cosmic time and suggest that our observational findings are consistent with the biased galaxy evolution scenario: a galaxy population hosted by massive dark haloes starts active star formation preferentially at early cosmic time, while less massive galaxies increase their number density later. We also calculated the UV luminosity density by integrating the UVLF and at z∼ 5 found it to be 38.8+6.7−4.1 per cent of that at z∼ 3 for the luminosity range L > 0.1L*z=3. By combining our results with those from the literature, we find that the cosmic UV luminosity density marks its peak at and then slowly declines towards higher redshift.

We present the results of new near-IR spectroscopic observations of passive galaxies at z 1.4 in a concentration of BzK-selected galaxies in the COSMOS field. The observations have been conducted with Subaru/MOIRCS, and have resulted in absorption lines and/or continuum detection for 18 out of 34 objects. This allows us to measure spectroscopic redshifts for a sample that is almost complete to K AB = 21. COSMOS photometric redshifts are found in fair agreement overall with the spectroscopic redshifts, with a standard deviation of ∼ 0.05; however, ∼ 30% of objects have photometric redshifts systematically underestimated by up to ∼ 25%. We show that these systematic offsets in photometric redshifts can be removed by using these objects as a training set. All galaxies fall in four distinct redshift spikes at z = 1.43, 1.53, 1.67 and 1.82, with this latter one including 7 galaxies. SED fits to broad-band fluxes indicate stellar masses in the range of ∼ 4-40 × 10 10 M ⊙ and that star formation was quenched ∼ 1 Gyr before the cosmic epoch at which they are observed. The spectra of several individual galaxies have allowed us to measure their Hδ F indices and the strengths of the 4000 Å break, which confirms their identification as passive galaxies, as does a composite spectrum resulting from the coaddition of 17 individual spectra. The effective radii of the galaxies have been measured on the COSMOS HST/ACS i F814W -band image, confirming the coexistence at these redshifts of passive galaxies which are substantially more compact than their local counterparts with others that follow the local effective radius-stellar mass relation. For the galaxy with best S/N spectrum we were able to measure a velocity dispersion of 270 ± 105 km s −1 (error bar including systematic errors), indicating that this galaxy lies closely on the virial relation given its stellar mass and effective radius.

We report a deficiency of luminous Lyman break galaxies (LBGs) with a large rest-frame equivalent width (EW rest ) of Lya emission at . Combining our spectroscopic sample of LBGs at and those from the z ∼ 5-6 z ∼ 5 literature, we found that luminous LBGs at generally show weak Lya emissions, while faint LBGs show z ∼ 5-6 a wide range of Lya EW rest and tend to have strong ( ) Lya emissions; i.e., there is a deficiencẙ EW տ 20 A rest of strong Lya emission in luminous LBGs. There seems to be a threshold UV luminosity for the deficiency; it is M 1400 p Ϫ21.5 to Ϫ21.0 mag, which is close to or somewhat brighter than the of the UV luminosity M * function at and 6. Since the large EW rest of Lya emission can be seen among the faint LBGs, the ratio of z ∼ 5 Lya emitters to LBGs may change rather abruptly with the UV luminosity. If the weakness of Lya emission is due to dust absorption, the deficiency suggests that luminous LBGs at tend to be in dusty and more z p 5-6 chemically evolved environments and that they begin star formation earlier than faint LBGs, although other causes cannot be ruled out.

We present the results of Spectral Energy Distribution (SED) fitting analysis for Lyman Break Galaxies (LBGs) at z ∼ 5 in the GOODS-N and its flanking fields (the GOODS-FF). With the publicly available IRAC images in the GOODS-N and IRAC data in the GOODS-FF, we constructed the rest-frame UV to optical SEDs for a large sample (∼ 100) of UV-selected galaxies at z ∼ 5. Comparing the observed SEDs with model SEDs generated with a population synthesis code, we derived a best-fit set of parameters (stellar mass, age, color excess, and star formation rate) for each of sample LBGs. The derived stellar masses range from 10 8 to 10 11 M ⊙ with a median value of 4.1 × 10 9 M ⊙ . The comparison with z = 2 − 3 LBGs shows that the stellar masses of z ∼ 5 LBGs are systematically smaller by a factor of 3 − 4 than those of z = 2 − 3 LBGs in a similar rest-frame UV luminosity range. The star formation ages are relatively younger than those of the z = 2 − 3 LBGs. We also compared the results for our sample with other studies for the z = 5 − 6 galaxies. Although there seem to be similarities and differences in the properties, we could not conclude its significance. We also derived a stellar mass function of our sample by correcting for incompletenesses. Although the number densities in the massive end are comparable to the theoretical predictions from semi-analytic models involving AGN feedback, the number densities in the low-mass part are smaller than the model predictions. By integrating the stellar mass function down to 10 8 M ⊙ , the stellar mass density at z ∼ 5 is calculated to be (0.7 − 2.4) × 10 7 M ⊙ Mpc −3 . The stellar mass density at z ∼ 5 is dominated by massive part of the stellar mass function. Compared with other observational studies and the model predictions, the mass density of our sample is consistent with general trend of the increase of the stellar mass density with time.