Christoffer Karoff
Dados Biográficos
| ID | 5597707 |
|---|---|
| NOME | Christoffer Karoff |
| PRENOMES | Christoffer |
| SOBRENOME | Karoff |
| ASSINATURA | KAROFF C |
| VERIFICADO | Não |
| TOTAL DE OBRAS | 5 |
| TOTAL DE CITAÇÕES | 18 |
| TOTAL COMO AUTOR | 5 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 2018 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2021 |
| ÍNDICE H | 3 |
Batch Processing of Tree-Ring Samples for Radiocarbon Analysis
We here present a comparison of methods for the pretreatment of a batch of tree rings for high-precision measurement of radiocarbon at the Aarhus AMS Centre (AARAMS), Aarhus University, Denmark. The aim was to develop an efficient and high-throughput method able to pretreat ca. 50 samples at a time. We tested two methods for extracting α-cellulose from wood to find the most optimal for our use. One method used acetic acid, the other used HCl acid…
An Intercomparison Project on 14 C From Single-Year Tree Rings
A laboratory intercomparison project was carried out on 20 annually resolved late-wood samples from the Danish oak record. The project included the following three laboratories: (1) the University of Arizona AMS Laboratory, University of Arizona, USA (AA); (2) HEKAL AMS Laboratory, MTA Atomki, Hungary (DeA); and (3) Aarhus AMS Centre (AARAMS), Aarhus University, Denmark (AAR). The large majority of individual data points (96%) lie within ±2σ of t…
Changes in Solar Activity During the Wolf Minimum—new Insights From a High-Resolution 14 C Record Based on Danish Oak
We present a new biennial record of radiocarbon ( 14 C) measured in Danish oak. The new record covers the years 1251–1378 CE, thereby spanning the Grand Solar Minimum known as the Wolf Minimum. Two oak samples from every other year were measured at the AMS facility at Aarhus University (Denmark), resulting in an average precision of 1.4‰ for the record. Spectral analysis of the new record revealed two peaks at 27 and 9.1 years, which could indica…
New Single-Year Radiocarbon Measurements Based on Danish oak Covering the Periods AD 692–790 and 966–1057
Single-year measurements of radiocarbon ( 14 C) in tree rings have led to the discovery of rapid cosmic-ray events as well as longer lasting anomalies, which have given new insights into the Sun’s behavior in the past. Here, we present two new single-year 14 C records based on Danish oak that span the periods AD 692–790 and 966–1057, respectively, and consequently include the two rapid cosmic-ray events in AD 775 and 994. The new data are present…
What Is the Carbon Origin of Early-Wood
Substantial amounts of annual radiocarbon ( 14 C) data have recently been produced with the purpose of increasing the time resolution of 14 C records used for constructing the calibration curve and for studying the occurrence of abrupt cosmic-ray events. In this study, we investigate if it is possible to resolve sub-annual scale changes in the atmospheric 14 C content by measuring radiocarbon in early-wood and late-wood fractions from Danish oak.…
What Is the Carbon Origin of Early-Wood
Substantial amounts of annual radiocarbon ( 14 C) data have recently been produced with the purpose of increasing the time resolution of 14 C records used for constructing the calibration curve and for studying the occurrence of abrupt cosmic-ray events. In this study, we investigate if it is possible to resolve sub-annual scale changes in the atmospheric 14 C content by measuring radiocarbon in early-wood and late-wood fractions from Danish oak.…
Batch Processing of Tree-Ring Samples for Radiocarbon Analysis
We here present a comparison of methods for the pretreatment of a batch of tree rings for high-precision measurement of radiocarbon at the Aarhus AMS Centre (AARAMS), Aarhus University, Denmark. The aim was to develop an efficient and high-throughput method able to pretreat ca. 50 samples at a time. We tested two methods for extracting α-cellulose from wood to find the most optimal for our use. One method used acetic acid, the other used HCl acid…
New Single-Year Radiocarbon Measurements Based on Danish oak Covering the Periods AD 692–790 and 966–1057
Single-year measurements of radiocarbon ( 14 C) in tree rings have led to the discovery of rapid cosmic-ray events as well as longer lasting anomalies, which have given new insights into the Sun’s behavior in the past. Here, we present two new single-year 14 C records based on Danish oak that span the periods AD 692–790 and 966–1057, respectively, and consequently include the two rapid cosmic-ray events in AD 775 and 994. The new data are present…
Changes in Solar Activity During the Wolf Minimum—new Insights From a High-Resolution 14 C Record Based on Danish Oak
We present a new biennial record of radiocarbon ( 14 C) measured in Danish oak. The new record covers the years 1251–1378 CE, thereby spanning the Grand Solar Minimum known as the Wolf Minimum. Two oak samples from every other year were measured at the AMS facility at Aarhus University (Denmark), resulting in an average precision of 1.4‰ for the record. Spectral analysis of the new record revealed two peaks at 27 and 9.1 years, which could indica…
What Is the Carbon Origin of Early-Wood
Substantial amounts of annual radiocarbon ( 14 C) data have recently been produced with the purpose of increasing the time resolution of 14 C records used for constructing the calibration curve and for studying the occurrence of abrupt cosmic-ray events. In this study, we investigate if it is possible to resolve sub-annual scale changes in the atmospheric 14 C content by measuring radiocarbon in early-wood and late-wood fractions from Danish oak.…
New Single-Year Radiocarbon Measurements Based on Danish oak Covering the Periods AD 692–790 and 966–1057
Single-year measurements of radiocarbon ( 14 C) in tree rings have led to the discovery of rapid cosmic-ray events as well as longer lasting anomalies, which have given new insights into the Sun’s behavior in the past. Here, we present two new single-year 14 C records based on Danish oak that span the periods AD 692–790 and 966–1057, respectively, and consequently include the two rapid cosmic-ray events in AD 775 and 994. The new data are present…
Batch Processing of Tree-Ring Samples for Radiocarbon Analysis
We here present a comparison of methods for the pretreatment of a batch of tree rings for high-precision measurement of radiocarbon at the Aarhus AMS Centre (AARAMS), Aarhus University, Denmark. The aim was to develop an efficient and high-throughput method able to pretreat ca. 50 samples at a time. We tested two methods for extracting α-cellulose from wood to find the most optimal for our use. One method used acetic acid, the other used HCl acid…
An Intercomparison Project on 14 C From Single-Year Tree Rings
A laboratory intercomparison project was carried out on 20 annually resolved late-wood samples from the Danish oak record. The project included the following three laboratories: (1) the University of Arizona AMS Laboratory, University of Arizona, USA (AA); (2) HEKAL AMS Laboratory, MTA Atomki, Hungary (DeA); and (3) Aarhus AMS Centre (AARAMS), Aarhus University, Denmark (AAR). The large majority of individual data points (96%) lie within ±2σ of t…
Changes in Solar Activity During the Wolf Minimum—new Insights From a High-Resolution 14 C Record Based on Danish Oak
We present a new biennial record of radiocarbon ( 14 C) measured in Danish oak. The new record covers the years 1251–1378 CE, thereby spanning the Grand Solar Minimum known as the Wolf Minimum. Two oak samples from every other year were measured at the AMS facility at Aarhus University (Denmark), resulting in an average precision of 1.4‰ for the record. Spectral analysis of the new record revealed two peaks at 27 and 9.1 years, which could indica…
Geology (5 obras) · Paleontology (5 obras) · Radiocarbon dating (5 obras) · Geography (3 obras) · Physics (3 obras) · Absolute dating (2 obras) · Archaeology (2 obras) · Archaeology and ancient environmental studies (2 obras) · Dendrochronology (2 obras) · Environmental Science (2 obras)